Tony Pearson is a Master Inventor and Senior IT Architect for the IBM Storage product line at the
IBM Executive Briefing Center in Tucson Arizona, and featured contributor
to IBM's developerWorks. In 2016, Tony celebrates his 30th year anniversary with IBM Storage. He is
author of the Inside System Storage series of books. This blog is for the open exchange of ideas relating to storage and storage networking hardware, software and services.
(Short URL for this blog: ibm.co/Pearson )
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Every year, I teach hundreds of sellers how to sell IBM storage products. I have been doing this since the late 1990s, and it is one task that has carried forward from one job to another as I transitioned through various roles from development, to marketing, to consulting.
This week, I am in the city of Taipei [Taipei] to teach Top Gun sales class, part of IBM's [Sales Training] curriculum. This is only my second time here on the island of Taiwan.
As you can see from this photo, Taipei is a large city with just row after row of buildings. The metropolitan area has about seven million people, and I saw lots of construction for more on my ride in from the airport.
The student body consists of IBM Business Partners and field sales reps eager to learn how to become better sellers. Typically, some of the students might have just been hired on, just finished IBM Sales School, a few might have transferred from selling other product lines, while others are established storage sellers looking for a refresher on the latest solutions and technologies.
I am part of the teach team comprised of seven instructors from different countries. Here is what the week entails for me:
Monday - I will present "Selling Scale-Out NAS Solutions" that covers the IBM SONAS appliance and gateway configurations, and be part of a panel discussion on Disk with several other experts.
Tuesday - I have two topics, "Selling Disk Virtualization Solutions" and "Selling Unified Storage Solutions", which cover the IBM SAN Volume Controller (SVC), Storwize V7000 and Storwize V7000 Unified products.
Wednesday - I will explain how to position and sell IBM products against the competition.
Thursday - I will present "Selling Infrastructure Management Solutions" and "Selling Unified Recovery Management Solutions", which focus on the IBM Tivoli Storage portfolio, including Tivoli Storage Productivity Center, Tivoli Storage Manager (TSM), and Tivoli Storage FlashCopy Manager (FCM). The day ends with the dreaded "Final Exam".
Friday - The students will present their "Team Value Workshop" presentations, and the class concludes with a formal graduation ceremony for the subset of students who pass. A few outstanding students will be honored with "Top Gun" status.
These are the solution areas I present most often as a consultant at the IBM Executive Briefing Center in Tucson, so I can provide real-life stories of different client situations to help illustrate my examples.
The weather here in Taipei calls for rain every day! I was able to take this photo on Sunday morning while it was still nice and clear, but later in the afternoon, we had quite the downpour. I am glad I brought my raincoat!
With all the announcements we had in June, it is easy for some of the more subtle enhancements to get overlooked. While I was at Orlando for the IBM Edge conference, I was able to blog about some of the key featured announcements. Then, later, when I got back from Orlando to Tucson, I was able to then blog about [More IBM Storage Announcements]. For IBM's Scale-Out Network Attach Storage (SONAS), I had simply:
"SONAS v1.3.2 adds support for management by the newly announced IBM Tivoli Storage Productivity Center v5.1 release. Also, IBM now officially supports Gateway configurations that have the storage nodes connected to XIV or Storwize V7000 disk systems. These gateway configurations offer new flexible choices and options for our ever-expanding set of clients."
In my defense, IBM numbers its software releasees with version.release.modification, so 1.3.2 is Version 1, Release 3, Modification 2. Generally, modification announcements don't get much attention. The big announcement for v1.3.0 of SONAS happened last October, see my blog post [October 2011 Announcements - Part I] or
the nice summary post [IBM Scale-out Network Attached Storage 1.3.0] from fellow blogger Roger Luethy.
Here is a diagram showing the three configurations of SONAS.
I have covered the SONAS Appliance model in depth in previous blogs, with options for fast and slow disk speeds, choice of RAID protection levels, a collection of enterprise-class software features provided at no additional charge, and interfaces to support a variety of third party backup and anti-virus checking software.
The basics haven't changed. The SONAS appliance consists of 2 to 32 interface nodes, 2 to 60 storage nodes, and up to 7,200 disk drives. The maximum configuration takes up 17 frames and holds 21.6PB of raw disk capacity, which is about 17PB usable space when RAID6 is configured. An interface nodes has one or two hex-core processors with up to 144GB of RAM to offer up to 3.5GB/sec performance each. This makes IBM SONAS the fastest performing and most scalable disk system in IBM's System Storage product line.
I thought I would go a bit deeper on the gateway models. These models support up to ten storage nodes, organized in pairs. The key difference is that instead of internal disk controllers, the storage nodes connect to external disk systems. There is enough space in the base SONAS rack to hold up to six interface nodes, or you can add a second rack if you need more interface nodes for increased performance.
SONAS with XIV gateway
XIV offers a clever approach to storage that allows for incredibly fast access to data on relatively slow 7200 RPM drives. By scattering data across all drives and taking advantage of parallel processing, rebuild times for a failed 3TB drive are less than 75 minutes. Compare that to typical rebuild times for 3TB drives that could take as much as 9-10 hours under active I/O loads!
In the configuration, each pair of storage nodes can connect to external SAN Fabric switches that then connect to one or two XIV storage systems. How simple is that? These can be the original XIV systems that support 1TB and 2TB drives, or the new XIV Gen3 systems that support 400GB Solid-state drives (SSD) and 3TB spinning disk drives. In both cases, you can acquire additional storage capacity as little as 12 drives at a time (one XIV module holds 12 drives).
The maximum configuration of ten XIV boxes could hold 1,800 drives. At 3TB drive per drive, that would be 2.4PB usable capacity.
The SONAS with XIV gateway does not require the XIV devices to be dedicated for SONAS purposes. Rather, you can assign some XIV storage space for the SONAS, and the rest is available for other servers. In this manner, SONAS just looks like another set of Linux-based servers to the XIV storage system. This in effect gives you "Unified Storage", with a full complement of NAS protocols from the SONAS side (NFS, CIFS, FTP, HTTPS, SCP) as well as block-based protocols directly from the XIV (FCP, iSCSI).
SONAS with Storwize V7000 gateway
The other gateway offering is the SONAS with Storwize V7000. Like the SONAS with XIV gateway model, you connect a pair of SONAS storage nodes to 1 or 2 Storwize V7000 disk systems. However, you do not need a SAN Fabric switch in between. You can instead connect the SONAS storage nodes directly to the Storwize V7000 control enclosures.
To acquire additional storage capacity, you can purchase a single drive at a time. That's right. Not 12 drives, or 60 drives, at a time, but one at a time. The Storwize V7000 supports a wide range of SSD, SAS and NL-SAS drives at different sizes, speeds and capacities. The drives can be configured into various RAID protection levels: RAID 0, 1, 3, 5, 6 and 10.
Each Storwize V7000 control enclosure can have up to nine expansion drawers. If you choose the 2.5-inch 24-bay models, you can have up to 480 drives per storage node pair, for a total of 2,400 drives. If you choose the 3.5-inch 12-bay models, you can have up to 240 drives per node pair, 1,200 drives total. At 3TB per drive, this could be 3.6PB of raw capacity. The usable PB would depend on which RAID level you selected. Of course, you don't have to limit yourself all to one size or the other. Feel free to mix 2.5-inch and 3.5-inch drawers to provide different storage pool capabilities.
All three SONAS configurations support Active Cloud Engine. This is a collection of features that differentiate SONAS from the other scale-out NAS wannabees in the marketplace:
Policy-driven Data Placement -- Different files can be directed to different storage pools. You no longer have to associate certain file systems to certain storage technologies.
High-speed Scan Engine -- SONAS can scan 10 million files per minute, per node. These scans can be used to drive data migration, backups, expirations, or replications, for example. It is over 100 times faster than traditional walk-the-directory-tree approaches employed by other NAS solutions.
Policy-driven Migration -- You can migrate files from one storage pool to another, based on age, days since last reference, size, and other criteria. The files can be moved from disk to disk, or move out of SONAS and stored on external media, such as tape or a virtual tape library. A lot of data stored on NAS systems is dormant, with little or no likelihood of being looked at again. Why waste money keeping that kind of data on expensive disk? With SONAS, you can move those files to tape can save lots of money. The files are stubbed in the SONAS file system, so that an access request to a file will automatically trigger a recall to fetch the data from tape back to the SONAS system.
Policy-driven Expiration -- SONAS can help you keep your system clean, by helping you decide what files should be deleted. This is especially useful for things like logs and traces that tend to just hang around until some deletes them manually.
WAN Caching -- This allows one SONAS to act as a "Cloud Storage Gateway" for another SONAS at a remote location connected by Wide Area Network (WAN). Let's say your main data center has a large SONAS repository of files, and a small branch office has a smaller SONAS. This allows all locations to have a "Global" view of the all the interconnected SONAS systems, with a high-speed user experience for local LAN-based access to the most recent and frequently used files.
If you want to learn more, see the [IBM SONAS landing page]. Next week, I will be across the Pacific Ocean in [Taipei], to teach IBM Top Gun class to sales reps and IBM Business Partners. "Selling SONAS" will be one of the topics I will be covering!
Tonight PBS plans to air Season 38, Episode 6 of NOVA, titled [Smartest Machine On Earth]. Here is an excerpt from the station listing:
"What's so special about human intelligence and will scientists ever build a computer that rivals the flexibility and power of a human brain? In "Artificial Intelligence," NOVA takes viewers inside an IBM lab where a crack team has been working for nearly three years to perfect a machine that can answer any question. The scientists hope their machine will be able to beat expert contestants in one of the USA's most challenging TV quiz shows -- Jeopardy, which has entertained viewers for over four decades. "Artificial Intelligence" presents the exclusive inside story of how the IBM team developed the world's smartest computer from scratch. Now they're racing to finish it for a special Jeopardy airdate in February 2011. They've built an exact replica of the studio at its research lab near New York and invited past champions to compete against the machine, a big black box code -- named Watson after IBM's founder, Thomas J. Watson. But will Watson be able to beat out its human competition?"
Like most supercomputers, Watson runs the Linux operating system. The system runs 2,880 cores (90 IBM Power 750 servers, four sockets each, eight cores per socket) to achieve 80 [TeraFlops]. TeraFlops is the unit of measure for supercomputers, representing a trillion floating point operations. By comparison, Hans Morvec, principal research scientist at the Robotics Institute of Carnegie Mellon University (CMU) estimates that the [human brain is about 100 TeraFlops]. So, in the three seconds that Watson gets to calculate its response, it would have processed 240 trillion operations.
Several readers of my blog have asked for details on the storage aspects of Watson. Basically, it is a modified version of IBM Scale-Out NAS [SONAS] that IBM offers commercially, but running Linux on POWER instead of Linux-x86. System p expansion drawers of SAS 15K RPM 450GB drives, 12 drives each, are dual-connected to two storage nodes, for a total of 21.6TB of raw disk capacity. The storage nodes use IBM's General Parallel File System (GPFS) to provide clustered NFS access to the rest of the system. Each Power 750 has minimal internal storage mostly to hold the Linux operating system and programs.
When Watson is booted up, the 15TB of total RAM are loaded up, and thereafter the DeepQA processing is all done from memory. According to IBM Research, "The actual size of the data (analyzed and indexed text, knowledge bases, etc.) used for candidate answer generation and evidence evaluation is under 1TB." For performance reasons, various subsets of the data are replicated in RAM on different functional groups of cluster nodes. The entire system is self-contained, Watson is NOT going to the internet searching for answers.
The weather has warmed up here in Tucson so I started my Spring Cleaning early this year and unearthed from my garage a [Bankers Box] full of floppy diskettes.
IBM invented the floppy disk back in 1971, and continued to make improvements and enhancements through the 1980s and 1990s. It will be one of the many inventions celebrated as part of IBM's Centennial (100-year) anniversary. Here is an example [T-shirt]
IBM needed a way to send out small updates and patches for microcode of devices out in client locations. IBM had drives that could write information, and sent out "read-only" drives to the customer locations to receive these updates. These were flexible plastic circles with a magnetic coating, and placed inside a square paper sleeve. Imagine a floppy disk the size of a piece of standard paper. The 8-inch floppy fit conveniently in a manila envelope, sendable by standard mail, and could hold nearly 80KB of data.
I've been using floppies for the past thirty years. Here's some of my fondest memories:
While still in high school, my friend Franz Kurath and I formed "Pearson Kurath Systems", a software development firm. We wrote computer programs to run on UNIX and Personal Computers for small businesses here in Tucson. Whenever we developed a clever piece of code, a subroutine or procedure, we would save it on a floppy disk and re-use it for our next project. We wrote in the BASIC language, and our databases were simple Comma-Separated-Variable (CSV) flat files.
The 5.25-inch floppies we used could hold 360KB, and were flexible like the 8-inch models. Later versions of these 5.25-inch floppies would be able to hold as much as 1.2MB of data. We would convert single-sided floppies into double-sided ones by cutting out a notch in the outer sleeve. Covering up the notches would mark them as read-only.
The 3.5-inch floppies were introduced with a hard plastic shell, with the selling point that you can slap on a mailing label and postage and send it "as is" without the need for a separate envelope. These new 3.5-inch floppies would carry "HD" for high density 720KB, and double-sided versions could hold 1.44MB of data. The term "diskette" was used to associate these new floppies with [hard-shelled tape cassettes]. Sliding a plastic tab would allow floppies to be marked "read-only". IBM has the patent on this clever invention.
Continuing our computer programming business in college, Franz and I took out a bank loan to buy our first Personal Computer, for over $5000 dollars USD. Until then, we had to use equipment belonging to each client. The banks we went to didn't understand why we needed a computer, and suggested we just track our expenses on traditional green-and-white ledger paper. Back then, peronsal computers were for balancing your checkbook, playing games and organizing your collection of cooking recipies. But for us, it was a production machine. A computer with both 5.25-inch and 3.5-inch drives could copy files from one format to another as needed. The boost in productivity paid for itself within months.
Apple launched its Macintosh computer in 1984, with a built-in 3.5-inch disk drive as standard equipment. Here is a YouTube video of an [astronaut ejecting a floppy disk] from an Apple computer in space.
In my senior year at the University of Arizona, my roommate Dave had borrowed my backpack to hold his lunch for a bike ride. He thought he had taken everything out, but forgot to remove my 3.5-inch floppy diskette containing files for my senior project. By the time he got back, the diskette was covered in banana pulp. I was able to rescue my data by cracking open the plastic outer shell, cleaning the flexible magnetic media in soapy water, placing it back into the plastic shell of a second diskette, and then copied the data off to a third diskette.
After graduating from college, Franz and I went our separate ways. I went to work for IBM, and Franz went to work for [Chiat/Day], the advertising agency famous for the 1984 Macintosh commercial. We still keep in touch through Facebook.
At IBM, I was given a 3270 terminal to do my job, and would not be assigned a personal computer until years later. Once I had a personal computer at home and at work, the floppy diskette became my "briefcase". I could download a file or document at work, take it home, work on it til the wee hours of the morning, and then come back the next morning with the updated effort.
To help prepare me for client visits and public speaking at conferences, IBM loaned me out to local schools to teach. This included teaching Computer Science 101 at Pima Community College. When asked by a student whether to use "disc" or "disk", I wrote a big letter "C" on the left side of the chalkboard, and a big letter "K" on the right side. If it is round, I told the students while pointing at the letter "C", like a CD-ROM or DVD, use "disc". If it has corners, pointing to corners of the letter "K", like a floppy diskette or hard disk drive, use "disk".
On one of my business trips to visit a client, we discovered the client had experienced a problem that we had just recently fixed. Normally, this would have meant cutting a Program Trouble Fix (PTF) to a 3480 tape cartridge at an IBM facility, and send it to the client by mail. Unwilling to wait, I offered to download the PTF onto a floppy diskette on my laptop, upload it from a PC connected to their systems, and apply it there. This involved a bit of REXX programming to deal with the differences between ASCII and EBCDIC character sets, but it worked, and a few hours later they were able to confirm the fix worked.
In 1998, Apple would signal the begining of the end of the floppy disk era, announcing their latest "iMac" would not come with an internal built-in floppy drive. David Adams has a great article on this titled [The iMac and the Floppy Drive: A Conspiracy Theory]. You can get external floppy drives that connect via USB, so not having an internal drive is no longer a big deal.
While teaching a Top Gun class to a mix of software and hardware sales reps, one of the students asked what a "U" was. He had noticed "2U" and "3U" next to various products and wondered what that was referring to. The "U" represents the [standard unit of measure for height of IT equipment in standard racks]. To help them visualize, I explained that a 5.25-inch floppy disk was "3U" in size, and a 3.5-inch floppy diskette was "2U". Thus, a "U" is 1.75 inches, the thinnest dimension on a two-by-four piece of lumber. Servers that were only 1U tall would be referred to as "pizza boxes" for having similar dimensions.
Every year, right around November or so, my friends and family bring me their old computers for me to wipe clean. Either I would re-load them with the latest Ubuntu Linux so that their kids could use it for homework, or I would donate it to charity. Last November, I got a computer that could not boot from a CD-ROM, forcing me to build a bootable floppy. This gave me a chance to check out the various 1-disk and 2-disk versions of Linux and other rescue disks. I also have a 3-disk set of floppies for booting OS/2 in command line mode.
So while this unexpected box of nostalgia derailed my efforts to clean out my garage this weekend, it did inspire me to try to get some of the old files off them and onto my PC hard drive. I have already retrieved some low-res photographs, some emails I sent out, and trip reports I wrote. While floppy diskettes were notorious for being unreliable, and this box of floppies has been in the heat and cold for many Arizonan summers and winters, I am amazed that I was able to read the data off most of them so far, all the way back to data written in 1989. While the data is readable, in most cases I can't render it into useful information. This brings up a few valuable lessons:
Backups are not Archives
Some of the files are in proprietary formats, such as my backups for TurboTax software. I would need a PC running a correct level of Windows operating system, and that particular software, just to restore the data. TurboTax shipped new software every year, and I don't know how forward or backward-compatible each new release was.
Another set of floppies are labeled as being in "FDBACK" format. I have no idea what these are. Each floppy has just two files, "backup.001" and "control.001", for example.
Backups are intended solely to protect against unexpected loss from broken hardware or corrupted data. If you plan to keep data as archives for long-term retention, use archive formats that will last a long time, so that you can make sense of them later.
Operating System Compatibility
Windows 7 and all of my favorite flavors of Linux are able to recognize the standard "FAT" file system that nearly all of my floppies are written in. Sadly, I have some files that were compressed under OS/2 operating system using software called "Stacker". I may have to stand up an OS/2 machine just to check out what is actually on those floppies.
You can't judge a book by its cover
Floppies were a convenient form of data interchange. Sometimes, I reused commercially-labeled floppies to hold personal files. So, just because a floppy says "America On-Line (AOL) version 2.5 Installation", I can't just toss it away. It might actually contain something else entirely. This means I need to mount each floppy to check on its actual contents.
So what will I do with the floppies I can't read, can't write, and can't format? I think I will convert them into a [retro set of coasters], to protect my new living room furniture from hot and cold beverages.
Continuing my week in Washington DC for the annual [2010 System Storage Technical University], I presented a session on Storage for the Green Data Center, and attended a System x session on Greening the Data Center. Since they were related, I thought I would cover both in this post.
Storage for the Green Data Center
I presented this topic in four general categories:
Drivers and Metrics - I explained the three key drivers for consuming less energy, and the two key metrics: Power Usage Effectiveness (PUE) and Data Center Infrastructure Efficiency (DCiE).
Storage Technologies - I compared the four key storage media types: Solid State Drives (SSD), high-speed (15K RPM) FC and SAS hard disk, slower (7200 RPM) SATA disk, and tape. I had comparison slides that showed how IBM disk was more energy efficient than competition, for example DS8700 consumes less energy than EMC Symmetrix when compared with the exact same number and type of physical drives. Likewise, IBM LTO-5 and TS1130 tape drives consume less energy than comparable HP or Oracle/Sun tape drives.
Integrated Systems - IBM combines multiple storage tiers in a set of integrated systems managed by smart software. For example, the IBM DS8700 offers [Easy Tier] to offer smart data placement and movement across Solid-State drives and spinning disk. I also covered several blended disk-and-tape solutions, such as the Information Archive and SONAS.
Actions and Next Steps - I wrapped up the talk with actions that data center managers can take to help them be more energy efficient, from deploying the IBM Rear Door Heat Exchanger, or improving the management of their data.
Greening of the Data Center
Janet Beaver, IBM Senior Manager of Americas Group facilities for Infrastructure and Facilities, presented on IBM's success in becoming more energy efficient. The price of electricity has gone up 10 percent per year, and in some locations, 30 percent. For every 1 Watt used by IT equipment, there are an additional 27 Watts for power, cooling and other uses to keep the IT equipment comfortable. At IBM, data centers represent only 6 percent of total floor space, but 45 percent of all energy consumption. Janet covered two specific data centers, Boulder and Raleigh.
At Boulder, IBM keeps 48 hours reserve of gasoline (to generate electricity in case of outage from the power company) and 48 hours of chilled water. Many power outages are less than 10 minutes, which can easily be handled by the UPS systems. At least 25 percent of the Computer Room Air Conditioners (CRAC) are also on UPS as well, so that there is some cooling during those minutes, within the ASHRAE guidelines of 72-80 degrees Fahrenheit. Since gasoline gets stale, IBM runs the generators once a month, which serves as a monthly test of the system, and clears out the lines to make room for fresh fuel.
The IBM Boulder data center is the largest in the company: 300,000 square feet (the equivalent of five football fields)! Because of its location in Colorado, IBM enjoys "free cooling" using outside air temperature 63 percent of the year, resulting in a PUE of 1.3 rating. Electricity is only 4.5 US cents per kWh. The center also uses 1 Million KwH per year of wind energy.
The Raleigh data center is only 100,000 Square feet, with a PUE 1.4 rating. The Raleigh area enjoys 44 percent "free cooling" and electricity costs at 5.7 US cents per kWh. The Leadership in Energy and Environmental Design [LEED] has been updated to certify data centers. The IBM Boulder data center has achieved LEED Silver certification, and IBM Raleigh data center has LEED Gold certification.
Free cooling, electricity costs, and disaster susceptibility are just three of the 25 criteria IBM uses to locate its data centers. In addition to the 7 data centers it manages for its own operations, and 5 data centers for web hosting, IBM manages over 400 data centers of other clients.
It seems that Green IT initiatives are more important to the storage-oriented attendees than the x86-oriented folks. I suspect that is because many System x servers are deployed in small and medium businesses that do not have data centers, per se.
The technology industry is full of trade-offs. Take for example solar cells that convert sunlight to electricity. Every hour, more energy hits the Earth in the form of sunlight than the entire planet consumes in an entire year. The general trade-off is between energy conversion efficiency versus abundance of materials:
Get 9-11 percent efficiency using rare materials like indium (In), gallium (Ga) or cadmium (Cd).
Get only 6.7 percent efficiency using abundant materials like copper (Cu), tin (Sn), zinc (Zn), sulfur (S), and selenium (Se)
A second trade-off is exemplified by EMC's recent GeoProtect announcement. This appears similar to the geographic dispersal method introduced by a company called [CleverSafe]. The trade-off is between the amount of space to store one or more copies of data and the protection of data in the event of disaster. Here's an excerpt from fellow blogger Chuck Hollis (EMC) titled ["Cloud Storage Evolves"]:
"Imagine a average-sized Atmos network of 9 nodes, all in different time zones around the world. And imagine that we were using, say, a 6+3 protection scheme.
The implication is clear: any 3 nodes could be completely lost: failed, destroyed, seized by the government, etc.
-- and the information could be completely recovered from the surviving nodes."
For organizations worried about their information falling into the wrong hands (whether criminal or government sponsored!), any subset of the nodes would yield nothing of value -- not only would the information be presumably encrypted, but only a few slices of a far bigger picture would be lost.
Seized by the government?falling into the wrong hands? Is EMC positioning ATMOS as "Storage for Terrorists"? I can certainly appreciate the value of being able to protect 6PB of data with only 9PB of storage capacity, instead of keeping two copies of 6PB each, the trade-off means that you will be accessing the majority of your data across your intranet, which could impact performance. But, if you are in an illicit or illegal business that could have a third of your facilities "seized by the government", then perhaps you shouldn't house your data centers there in the first place. Having two copies of 6PB each, in two "friendly nations", might make more sense.
(In reality, companies often keep way more than just two copies of data. It is not unheard of for companies to keep three to five copies scattered across two or three locations. Facebook keeps SIX copies of photographs you upload to their website.)
ChuckH argues that the governments that seize the three nodes won't have a complete copy of the data. However, merely having pieces of data is enough for governments to capture terrorists. Even if the striping is done at the smallest 512-byte block level, those 512 bytes of data might contain names, phone numbers, email addresses, credit cards or social security numbers. Hackers and computer forensics professionals take advantage of this.
You might ask yourself, "Why not just encrypt the data instead?" That brings me to the third trade-off, protection versus application performance. Over the past 30 years, companies had a choice, they could encrypt and decrypt the data as needed, using server CPU cycles, but this would slow down application processing. Every time you wanted to read or update a database record, more cycles would be consumed. This forced companies to be very selective on what data they encrypted, which columns or fields within a database, which email attachments, and other documents or spreadsheets.
An initial attempt to address this was to introduce an outboard appliance between the server and the storage device. For example, the server would write to the appliance with data in the clear, the appliance would encrypt the data, and pass it along to the tape drive. When retrieving data, the appliance would read the encrypted data from tape, decrypt it, and pass the data in the clear back to the server. However, this had the unintended consequences of using 2x to 3x more tape cartridges. Why? Because the encrypted data does not compress well, so tape drives with built-in compression capabilities would not be able to shrink down the data onto fewer tapes.
(I covered the importance of compressing data before encryption in my previous blog post
[Sock Sock Shoe Shoe].)
Like the trade-off between energy efficiency and abundant materials, IBM eliminated the trade-off by offering compression and encryption on the tape drive itself. This is standard 256-bit AES encryption implemented on a chip, able to process the data as it arrives at near line speed. So now, instead of having to choose between protecting your data or running your applications with acceptable performance, you can now do both, encrypt all of your data without having to be selective. This approach has been extended over to disk drives, so that disk systems like the IBM System Storage DS8000 and DS5000 can support full-disk-encryption [FDE] drives.
Well, it's Tuesday again, and we have more IBM announcements.
XIV asynchronous mirror
For those not using XIV behind SAN Volume Controller, [XIV now offers native asynchronous mirroring] support to another XIV far, far away. Unlike other disk systems that are limited to two or three sites, an XIV can mirror to up to 15 other sites. The mirroring can be at the individual volume, or a consistency group of multiple volumes. Each mirror pair can have its own recovery point objective (RPO). For example, a consistency group of mission critical application data might be given an RPO of 30 seconds, but less important data might be given an RPO of 20 minutes. This allows the XIV to prioritize packets it sends across the network.
As with XIV synchronous mirror, this new asynchronous mirror feature can send the data over either its
Fibre Channel ports (via FCIP) or its Ethernet ports.
The IBM System Storage SAN384B and SAN768B directors now offer [two new blades!]
A 24-port FCoCEE blade where each port can handle 10Gb convergence enhanced Ethernet (CEE). CEE can be used to transmit Fibre Channel, TCP/IP, iSCSI and other Ethernet protocols. This connect directly to server's converged network adapter (CNA) cards.
A 24-port mixed blade, with 12 FC ports (1Gbps, 2Ggbs, 4Gbps, 8Gbps), 10 Ethernet ports (1GbE) and 2 Ethernet ports (10GbE). This would connect to traditional server NIC, TOE and HBA cards as well as traditional NAS, iSCSI and FC based storage devices.
IBM also announced the IBM System Storage [SAN06B-R Fibre Channel router]. This has 16 FC ports (1Gbps up to 8Gbps) and six Ethernet ports (1GbE), with support for both FC routing as well as FCIP extended distance support.
With the holiday season coming up at the end of the year, now is a great time to ask Santa for a new shiny pair of XIV systems, and some extra networking gear to connect them.
Well, it's Tuesday again, but this time, today we had our third big storage launch of 2009! A lot got announced today as part of IBM's big "Dynamic Infrastructure" marketing campaign. I will just focus on the
disk-related announcements today:
IBM System Storage DS8700
IBM adds a new model to its DS8000 series with the
[IBM System Storage DS8700]. Earlier this month, fellow blogger and arch-nemesis Barry Burke from EMC posted [R.I.P DS8300] on this mistaken assumption that the new DS8700 meant that DS8300 was going away, or that anyone who bought a DS8300 recently would be out of luck. Obviously, I could not respond until today's announcement, as the last thing I want to do is lose my job disclosing confidential information. BarryB is wrong on both counts:
IBM will continue to sell the DS8100 and DS8300, in addition to the new DS8700.
Clients can upgrade their existing DS8100 or DS8300 systems to DS8700.
BarryB's latest post [What's In a Name - DS8700] is fair game, given all the fun and ridicule everyone had at his expense over EMC's "V-Max" name.
So the DS8700 is new hardware with only 4 percent new software. On the hardware side, it uses faster POWER6 processors instead of POWER5+, has faster PCI-e buses instead of the RIO-G loops, and faster four-port device adapters (DAs) for added bandwidth between cache and drives. The DS8700 can be ordered as a single-frame dual 2-way that supports up to 128 drives and 128GB of cache, or as a dual 4-way, consisting of one primary frame, and up to four expansion frames, with up to 384GB of cache and 1024 drives.
Not mentioned explicitly in the announcements were the things the DS8700 does not support:
ESCON attachment - Now that FICON is well-established for the mainframe market, there is no need to support the slower, bulkier ESCON options. This greatly reduced testing effort. The 2-way DS8700 can support up to 16 four-port FICON/FCP host adapters, and the 4-way can support up to 32 host adapters, for a maximum of 128 ports. The FICON/FCP host adapter ports can auto-negotiate between 4Gbps, 2Gbps and 1Gbps as needed.
LPAR mode - When IBM and HDS introduced LPAR mode back in 2004, it sounded like a great idea the engineers came up with. Most other major vendors followed our lead to offer similar "partitioning". However, it turned out to be what we call in the storage biz a "selling apple" not a "buying apple". In other words, something the salesman can offer as a differentiating feature, but that few clients actually use. It turned out that supporting both LPAR and non-LPAR modes merely doubled the testing effort, so IBM got rid of it for the DS8700.
Update: I have been reminded that both IBM and HDS delivered LPAR mode within a month of each other back in 2004, so it was wrong for me to imply that HDS followed IBM's lead when obviously development happened in both companies for the most part concurrently prior to that. EMC was late to the "partition" party, but who's keeping track?
Initial performance tests show up to 50 percent improvement for random workloads, and up to 150 percent improvement for sequential workloads, and up to 60 percent improvement in background data movement for FlashCopy functions. The results varied slightly between Fixed Block (FB) LUNs and Count-Key-Data (CKD) volumes, and I hope to see some SPC-1 and SPC-2 benchmark numbers published soon.
The DS8700 is compatible for Metro Mirror, Global Mirror, and Metro/Global Mirror with the rest of the DS8000 series, as well as the ESS model 750, ESS model 800 and DS6000 series.
New 600GB FC and FDE drives
IBM now offers [600GB drives] for the DS4700 and DS5020 disk systems, as well as the EXP520 and EXP810 expansion drawers. In each case, we are able to pack up to 16 drives into a 3U enclosure.
Personally, I think the DS5020 should have been given a DS4xxx designation, as it resembles the DS4700
more than the other models of the DS5000 series. Back in 2006-2007, I was the marketing strategist for IBM System Storage product line, and part of my job involved all of the meetings to name or rename products. Mostly I gave reasons why products should NOT be renamed, and why it was important to name the products correctly at the beginning.
IBM System Storage SAN Volume Controller hardware and software
Fellow IBM master inventory Barry Whyte has been covering the latest on the [SVC 2145-CF8 hardware]. IBM put out a press release last week on this, and today is the formal announcement with prices and details. Barry's latest post
[SVC CF8 hardware and SSD in depth] covers just part of the entire
The other part of the announcement was the [SVC 5.1 software] which can be loaded
on earlier SVC models 8F2, 8F4, and 8G4 to gain better performance and functionality.
To avoid confusion on what is hardware machine type/model (2145-CF8 or 2145-8A4) and what is software program (5639-VC5 or 5639-VW2), IBM has introduced two new [Solution Offering Identifiers]:
5465-028 Standard SAN Volume Controller
5465-029 Entry Edition SAN Volume Controller
The latter is designed for smaller deployments, supports only a single SVC node-pair managing up to
150 disk drives, available in Raven Black or Flamingo Pink.
EXN3000 and EXP5060 Expansion Drawers
IBM offers the [EXN3000 for the IBM N series]. These expansion drawers can pack 24 drives in a 4U enclosure. The drives can either be all-SAS, or all-SATA, supporting 300GB, 450GB, 500GB and 1TB size capacity drives.
The [EXP5060 for the IBM DS5000 series] is a high-density expansion drawer that can pack up to 60 drives into a 4U enclosure. A DS5100 or DS5300
can handle up to eight of these expansion drawers, for a total of 480 drives.
Pre-installed with Tivoli Storage Productivity Center Basic Edition. Basic Edition can be upgraded with license keys to support Data, Disk and Standard Edition to extend support and functionality to report and manage XIV, N series, and non-IBM disk systems.
Pre-installed with Tivoli Key Lifecycle Manager (TKLM). This can be used to manage the Full Disk Encryption (FDE) encryption-capable disk drives in the DS8000 and DS5000, as well as LTO and TS1100 series tape drives.
IBM Tivoli Storage FlashCopy Manager v2.1
The [IBM Tivoli Storage FlashCopy Manager V2.1] replaces two products in one. IBM used
to offer IBM Tivoli Storage Manager for Copy Services (TSM for CS) that protected Windows application data, and IBM Tivoli Storage Manager for Advanced Copy Services (TSM for ACS) that protected AIX application data.
The new product has some excellent advantages. FlashCopy Manager offers application-aware backup of LUNs containing SAP, Oracle, DB2, SQL server and Microsoft Exchange data. It can support IBM DS8000, SVC and XIV point-in-time copy functions, as well as the Volume Shadow Copy Services (VSS) interfaces of the IBM DS5000, DS4000 and DS3000 series disk systems. It is priced by the amount of TB you copy, not on the speed or number of CPU processors inside the server.
Don't let the name fool you. IBM FlashCopy Manager does not require that you use Tivoli Storage Manager (TSM) as your backup product. You can run IBM FlashCopy Manager on its own, and it will manage your FlashCopy target versions on disk, and these can be backed up to tape or another disk using any backup product. However, if you are lucky enough to also be using TSM, then there is optional integration that allows TSM to manage the target copies, move them to tape, inventory them in its DB2 database, and provide complete reporting.
Yup, that's a lot to announce in one day. And this was just the disk-related portion of the launch!
I am proud to announce we have yet another IBM blogger for the storosphere, Rich Swain from IBM's Research Triangle Park in Raleigh, North Carolina will blog about
[News and Information on IBM’s N series].
Rich is a Field Technical Sales Specialist with deep-dive knowledge and experience.
He's already posted a dozen or so entries, to give you a feel for the level of technical detail he will provide.
Please welcome Rich by following his blog and posting comments on his posts.
Well, it's Wednesday! Normally, IBM makes its announcements on Tuesday's, but this week that landed on the 13th, and some people are superstitious, so we pushed it back to today. Fellow IBM master inventory Barry Whyte starts the first in a series of posts with: New SVC v5 CF8 node with native SSD support.
There are really two separate items being announced for the IBM System Storage SAN Volume Controller (SVC):
SVC v5 software
The software moves from a 32-bit kernel to a 64-bit kernel. Fortunately, IBM had the foresight to know that would happen back in 2005, so models 8F2, 8F4 and 8G4 can be upgrade to this new software level and gain new functionality. This is because these models have 64-bit capable processors. Those with six-year-old 4F2 will continue to run on SVC 4.3.1, but should consider it's about time to upgrade soon.
New 2145-CF8 model
The CF8 is based on the IBM System x 3550M2. Each node can have up to 4 Solid-State Drives (SSD) that can be treated as SVC Managed Disk Groups. Virtual disks can be easily migrated from hard disk drives (HDD) over to SSD, processed, and then move them back to HDD. By treating the SSD as managed disks, rather than an extension of the cache, we are able to support all of the features and functions in a seamless manner.
As Barry says, IBM has been working on this for quite a while, and based on initial responses looks to be quite successful in the market!
Well, it's Tuesday, and that means IBM announcements! Today is bigger, as there are a lot of Dynamic Infrastructure announcements throughout the company with a common theme, cloud computing and smart business systems that support the new way of doing things. Today, IBM announced its new "IBM Smart Archive" strategy that integrates software, storage, servers and services into solutions that help meet the challenges of today and tomorrow. IBM has been spending the past few years working across its various divisions and acquisitions to ensure that our clients have complete end-to-end solutions.
IBM is introducing new "Smart Business Systems" that can be used on-premises for private-cloud configurations, as well as by cloud-computing companies to offer IT as a service.
IBM [Information Archive] is the first to be unveiled, a disk-only or blended disk-and-tape Information Infrastructure solution that offers a "unified storage" approach with amazing flexibility for dealing with various archive requirements:
For those with applications using the IBM Tivoli Storage Manager (TSM) or IBM System Storage Archive Manager (SSAM) API of the IBM System Storage DR550 data retention solution, the Information Archive will provide a direct migration, supporting this API for existing applications.
For those with IBM N series using SnapLock or the File System Gateway of the DR550, the Information Archive will support various NAS protocols, deployed in stages, including NFS, CIFS, HTTP and FTP access, with Non-Erasable, Non-Rewriteable (NENR) enforcement that are compatible with current IBM N series SnapLock usage.
For those using NAS devices with PACS applications to store X-rays and other medical images, the Information Archive will provide similar NAS protocol interfaces. Information Archive will support both read-only data such as X-rays, as well as read/write data such as Electronic Medical Records.
Information Archive is not just for compliance data that was previously sent to WORM optical media. Instead, it can handle all kinds of data, rewriteable data, read-only data, and data that needs to be locked down for tamper protection. It can handle structured databases, emails, videos and unstructured files, as well as objects stored through the SSAM API.
The Information Archive has all the server, storage and software integrated together into a single machine type/model number. It is based on IBM's General Parallel File System (GPFS) to provide incredible scalability, the same clustered file system used by many of the top 500 supercomputers. Initially, Information Archive will support up to 304TB raw capacity of disk and Petabytes of tape. You can read the [Spec Sheet] for other technical details.
For those who prefer a more "customized" approach, similar to IBM Scale-Out File Services (SoFS), IBM has [Smart Business Storage Cloud]. IBM Global Services can customize a solution that is best for you, using many of the same technologies. In fact, IBM Global Services announced a variety of new cloud-computing services to help enterprises determine the best approach.
In a related announcement, IBM announced [LotusLive iNotes], which you can think of as a "business-ready" version of Google's GoogleApps, Gmail and GoogleCalendar. IBM is focused on security and reliability but leaves out the advertising and data mining that people have been forced to tolerate from consumer-oriented Web 2.0-based solutions. IBM's clients that are already familiar with on-premises version of Lotus Notes will have no trouble using LotusLive iNotes.
There was actually a lot more announced today, which I will try to get to in later posts.
Well, it's Tuesday again, and that means IBM announcements!
We've got a variety of storage-related items today, so here's my quick recap:
DS5020 and EXP520 disk systems
[IBM System Storage DS5020]
provides the functional replacement for DS4700 disk systems. These are combined controller
and 16 drives in a compact 3U package.
The EXP520 expansion drawer provides additional 16 drives per 3U drawer. A DS5020 can
support upo to six additional EXP520, for a total of 112 drives per system.
The DS5020 supports both 8 Gbps FC as well as 1GbE iSCSI.
New Remote Support Manager (DS-RSM model RS2)
The [IBM System Storage DS-RSM Model
RS2] supports of up to 50 disk systems, any mix of DS3000, DS4000 and DS5000 series.
It includes "call home" support, which is really "email home", sending error alerts to IBM
if there are any problems. The RSM also allows IBM to dial-in to perform diagnostics before
arrival, reducing the time needed to resolve a problem. The model RS2 is a beefier model
with more processing power than the prior generation RS1.
New Ethernet Switches
With the increased interest in iSCSI protocol, and the new upcoming Fibre Channel over
Convergence Enhanced Ethernet (FCoCEE), IBM's re-entrance into the ethernet switch market
has drawn a lot of interest.
The [IBM Ethernet Switch r-
series] offers 4-slot, 8-slot, 16-slot, and 32-slot models. Each slot can handle either
16 10GbE ports, or 48 1GbE ports. This means up to 1,536 ports.
The [c-series] now offers a
24-port model. This is either 24 copper and 4 fiber optic, or 24 fiber optic.
The "hybrid fiber" SFP fiber optic can handle either single or multi-mode, eliminating the
need to commit to one or the other, providing greater data center flexibility.
The [IBM Ethernet Switch B24X]
offers 24 fiber optic (that can handle 10GbE or 1GbE) and 4 copper (10/100/1000 MbE RJ45)
Storage Optimization and Integration Services
[IBM Storage Optimization and
Integration Services] are available. IBM service consultants use IBM's own
Storage Enterprise Resource Planner (SERP) software to evaluate your environment and provide
recommendations on how to improve your information infrastructure. This can be especially
helpful if you are looking at deploying server virtualization like VMware or Hyper-V.
As people look towards deploying a dynamic infrastructure, these new offerings can be a
Continuing my week in Chicago, for the IBM Storage Symposium 2008, we had sessions that focused on individual products. IBM System Storage SAN Volume Controller (SVC) was a popular topic.
SVC - Everything you wanted to know, but were afraid to ask!
Bill Wiegand, IBM ATS, who has been working with SAN Volume Controller since it was first introduced in 2003. answered some frequently asked questions about IBM System Storage SAN Volume Controller.
Do you have to upgrade all of your HBAs, switches and disk arrays to the recommended firmware levels before upgrading SVC? No. These are recommended levels, but not required. If you do plan to update firmware levels, focus on the host end first, switches next, and disk arrays last.
How do we request special support for stuff not yet listed on the Interop Matrix?
Submit an RPQ/SCORE, same as for any other IBM hardware.
How do we sign up for SVC hints and tips? Go to the IBM
[SVC Support Site] and select the "My Notifications" under the "Stay Informed" box on the right panel.
When we call IBM for SVC support, do we select "Hardware" or "Software"?
While the SVC is a piece of hardware, there are very few mechanical parts involved. Unless there are sparks,
smoke, or front bezel buttons dangling from springs, select "Software". Most of the questions are
related to the software components of SVC.
When we have SVC virtualizing non-IBM disk arrays, who should we call first?
IBM has world-renown service, with some of IT's smartest people working the queues. All of the major storage vendors play nice
as part of the [TSAnet Agreement when a mutual customer is impacted.
When in doubt, call IBM first, and if necessary, IBM will contact other vendors on your behalf to resolve.
What is the difference between livedump and a Full System Dump?
Most problems can be resolved with a livedump. While not complete information, it is generally enough,
and is completely non-disruptive. Other times, the full state of the machine is required, so a Full System Dump
is requested. This involves rebooting one of the two nodes, so virtual disks may temporarily run slower on that
What does "svc_snap -c" do?The "svc_snap" command on the CLI generates a snap file, which includes the cluster error log and trace files from all nodes. The "-c" parameter includes the configuration and virtual-to-physical mapping that can be useful for
disaster recovery and problem determination.
I just sent IBM a check to upgrade my TB-based license on my SVC, how long should I wait for IBM to send me a software license key?
IBM trusts its clients. No software license key will be sent. Once the check clears, you are good to go.
During migration from old disk arrays to new disk arrays, I will temporarily have 79TB more disk under SVC management, do I need to get a temporary TB-based license upgrade during the brief migration period?
Nope. Again, we trust you. However, if you are concerned about this at all, contact IBM and they will print out
a nice "Conformance Letter" in case you need to show your boss.
How should I maintain my Windows-based SVC Master Console or SSPC server?
Treat this like any other Windows-based server in your shop, install Microsoft-recommended Windows updates,
run Anti-virus scans, and so on.
Where can I find useful "How To" information on SVC?
Specify "SAN Volume Controller" in the search field of the
[IBM Redbooks vast library of helpful books.
I just added more managed disks to my managed disk group (MDG), can I get help writing a script to redistribute the extents to improve wide-striping performance?
Yes, IBM has scripting tools available for download on
[AlphaWorks]. For example, svctools will take
the output of the "lsinfo" command, and generate the appropriate SVC CLI to re-migrate the disks around to optimize
performance. Of course, if you prefer, you can use IBM Tivoli Storage Productivity Center instead for a more
Any rules of thumb for sizing SVC deployments?
IBM's Disk Magic tool includes support for SVC deployments. Plan for 250 IOPS/TB for light workloads,
500 IOPS/TB for average workloads, and 750 IOPS/TB for heavy workloads.
Can I migrate virtual disks from one manage disk group (MDG) to another of different extent size?
Yes, the new Vdisk Mirroring capability can be used to do this. Create the mirror for your Vdisk between the
two MDGs, wait for the copy to complete, and then split the mirror.
Can I add or replace SVC nodes non-disruptively? Absolutely, see the Technotes
[SVC Node Replacement page.
Can I really order an SVC EE in Flamingo Pink? Yes. While my blog post that started all
this [Pink It and Shrink It] was initially just some Photoshop humor, the IBM product manager for SVC accepted this color choice as an RPQ option.
The default color remains Raven Black.
Continuing my week in Chicago, for the IBM Storage Symposium 2008, I attended two presentations on XIV.
XIV Storage - Best Practices
Izhar Sharon, IBM Technical Sales Specialist for XIV, presented best practices using XIV in various environments.He started out explaining the innovative XIV architecture: a SATA-based disk system from IBM can outperformFC-based disk systems from other vendors using massive parallelism. He used a sports analogy:
"The men's world record for running 800 meters was set in 1997 by Wilson Kipketer of Denmark in a time of 1:41.11.
However, if you have eight men running, 100 meters each, they will all cross the finish line in about 10 seconds."
Since XIV is already self-tuning, what kind of best practices are left to present? Izhar presented best practicesfor software, hosts, switches and storage virtualization products that attach to the XIV. Here's some quickpoints:
Use as many paths as possible.
IBM does not require you to purchase and install multipathing software as other competitors might. Instead, theXIV relies on multipathing capabilities inherent to each operating system.For multipathing preference, choose Round-Robin, which is now available onAIX and VMware vSphere 4.0, for example. Otherwise, fixed-path is preferred over most-recently-used (MRU).
Encourage parallel I/O requests.
XIV architecture does not subscribe to the outdated notion of a "global cache". Instead, the cache is distributed across the modules, to reduce performance bottlenecks. Each HBA on the XIV can handle about 1400requests. If you have fewer than 1400 hosts attached to the XIV, you can further increase parallel I/O requests by specifying a large queue depth in the host bus adapter (HBA).An HBA queue depth of 64 is a good start. Additional settings mightbe required in the BIOS, operating system or application for multiple threads and processes.
For sequential workloads, select host stripe size less than 1MB. For random, select host stripe size larger than 1MB. Set rr_min_io between ten(10) and the queue depth(typically 64), setting it to half of the queue depth is a good starting point.
If you have long-running batch jobs, consider breaking them up into smaller steps and run in parallel.
Define fewer, larger LUNs
Generally, you no longer need to define many small LUNs, a practice that was often required on traditionaldisk systems. This means that you can now define just 1 or 2 LUNs per application, and greatly simplifymanagement. If your application must have multiple LUNs in order to do multiple threads or concurrent I/O requests, then, by all means, define multiple LUNs.
Modern Data Base Management Systems (DBMS) like DB2 and Oracle already parallelize their I/O requests, sothere is no need for host-based striping across many logical volumes. XIV already stripes the data for you.If you use Oracle Automated Storage Management (ASM), use 8MB to 16MB extent sizes for optimal performance.
For those virtualizing XIV with SAN Volume Controller (SVC), define manage disks as 1632GB LUNs, in multiple of six LUNs per managed disk group (MDG), to balance across the six interface modules. Define SVC extent size to 1GB.
XIV is ideal for VMware. Create big LUNs for your VMFS that you can access via FCP or iSCSI.
Organize data to simplify Snapshots.
You no longer need to separate logs from databases for performance reasons. However, for some backup productslike IBM Tivoli Storage Manager (TSM) for Advanced Copy Services (ACS), you might want to keep them separatefor snapshot reasons. Gernally, putting all data for an application on one big LUNgreatly simplifies administration and snapshot processing, without losing performance.If you define multiple LUNs for an application, simply put them into the same "consistencygroup" so that they are all snapshot together.
OS boot image disks can be snapshot before applying any patches, updates or application software, so that ifthere are any problems, you can reboot to the previous image.
Employ sizing tools to plan for capacity and performance.
The SAP Quicksizer tool can be used for new SAP deployments, employing either the user-based orthroughput-based sizing model approach. The result is in mythical unit called "SAPS", which represents0.4 IOPS for ERP/OLTP workloads, and 0.6 IOPS for BI/BW and OLAP workloads.
If you already have SAP or other applications running, use actual I/O measurements. IBM Business Partners and field technical sales specialists have an updated version of Disk Magic that can help size XIV configurations fromPERFMON and iostat figures.
Lee La Frese, IBM STSM for Enteprise Storage Performance Engineering, presented internal lab test results forthe XIV under various workloads, based on the latest hardware/software levels [announced two weeks ago]. Three workloadswere tested:
Web 2.0 (80/20/40) - 80 percent READ, 20 percent WRITE, 40 percent cache hits for READ.YouTube, FlickR, and the growing list at [GoWeb20] are applications with heavy read activity, but because of[long-tail effects], may not be as cache friendly.
Social Networking (50/50/50) - 50 percent READ, 50 percent WRITE, 50 percent cache hits for READ.Lotus Connections, Microsoft Sharepoint, and many other [social networking] usage are more write intensive.
Database (70/30/50) - 70 percent READ, 30 percent WRITE, 50 percent cache hits for READ.The traditional workload characteristics for most business applications, especially databases like DB2 andOracle on Linux, UNIX and Windows servers.
The results were quite impressive. There was more than enough performance for tier 2 application workloads,and most tier 1 applications. The performance was nearly linear from the smallest 6-module to the largest 15-module configuration. Some key points:
A full 15-module XIV overwhelms a single SVC 8F4 node-pair. For a full XIV, consider 4 to 8 nodes 8F4 models, or 2 to 4 nodes of an 8G4. For read-intensive cache-friendly workloads, an SVC in front of XIV was able to deliver over 300,000 IOPS.
A single node TS7650G ProtecTIER can handle 6 to 9 XIV modules. Two nodes of TS7650G were needed to drivea full 15-module XIV. A single node TS7650 in front of XIV was able to ingest 680 MB/sec on the seventh day with17 percent per-day change rate test workload using 64 virtual drives. Reading the data back got over 950 MB/sec.
For SAP environments where response time 20-30 msec are acceptable, the 15-module XIV delivered over 60,000 IOPS. Reducing this down to 25,000-30,000 cut the msec response time to a faster 10-15 msec.
These were all done as internal lab tests. Your mileage may vary.
Not surprisingly, XIV was quite the popular topic here this week at the Storage Symposium. There were many moresessions, but these were the only two that I attended.
Continuing my week in Chicago, for the IBM Storage Symposium 2008, I attended several sessions intended to answer the questions of the audience.
In an effort to be cute, the System x team have a "Meet the xPerts" session at their System x and BladeCenter Technical Conference, so the storage side decided to do the same. Traditionally, these have been called "Birds of a Feature", "Q&A Panel", or "Free-for-All". They allow anyone to throw out a question, and have the experts in the room, either
IBM, Business Partner or another client, answer the question from their experience.
Meet the Experts - Storage for z/OS environments
Here were some of the questions answered:
I've seen terms like "z/OS", "zSeries" and "System z" used interchangeably, can you help clarify what this particular session is about?
IBM's current mainframe servers are all named "System z", such as our System z9 or System z10. These replace the older zSeries models of hardware. z/OS is one of the six operating systems that run on this hardware platform. The other five are z/VM, z/VSE, z/TPF, Linux and OpenSolaris. The focus of this session will be storage attached and used for z/OS specifically, including discussions of Omegamon and DFSMS software products.
What can we do to reduce our MIPS-based software licensing costs from our third party vendors?
Consider using IBM System z Integrated Information Processor
What about 8 Gbps FICON?
IBM has already announced
[FICON Express8] host bus adapter (HBA) cards, that will auto-negotiate to 4Gbps and 2Gbps speeds. If you don't need full 8Gbps speed now, you can
still get the Express8 cards, but put 4/2/1 Gbps SFP ports instead. Currently, LongWave (LW) is only supported to 4km at 8Gbps speed.
I want to use Global Mirror for my DS8100 to my remote DS8100, but also make test copies of my production data to
an older ESS 800 I have locally. Any suggestions? Yes, consider using FlashCopy to simplify this process.
I have Global Mirror (GM) running now successfully with DSCLI, and now want to deploy IBM Tivoli Storage Productivity Center for Replication. Is that possible? Yes, Productivity Center for Replication will detect existing GM relationships, and start managing them.
I have already deployed HyperPAV and zHPF, is there any value in getting Solid-State Drives as well?
HyperPAV and zHPF impact CONN time, but SSD impacts DISC time, so they are mutually complementary.
How should I size my FlashCopy SE pool? SE refers to "Space Efficient", which stores only the changes
between the source and destination copies of each LUN or CKD volume involved. General recommendation is to start with 20 percent and adjust accordingly.
How many RAID ranks should I configure per DS8000 extent pool? IBM recommends 4 to 8 ranks per pool.
Meet the Experts: Storage for Linux, UNIX and Windows distributed systems
This session was focused on storage systems attached to distributed servers, as well as products from Tivoli used to manage them. Here were some of the questions answered:
When we migrated from Tivoli Storage Manager v5 to v6, we lost our favorite "Operational Reporting" tool. How can we get TOR back? You now get the new Tivoli Common Reporting tool.
How can we identify appropriate port distribution for multiple SVC node pairs for load balancing?
IBM Tivoli Storage Productivity Center v4.1 has hot-spot analysis with recommendations for Vdisk migrations.
We tried TotalStorage Productivity Center way back when, but the frequent upgrades were killing us. How has it been lately? It has been much more stable since v3.3, and completely renamed to Tivoli Storage Productivity Center to avoid association with versions 1 and 2 of the predecessor product. The new "lightweight agents" feature of v4.1 resolve many of the problems you were experiencing.
We have over 1600 SVC virtual disks, how do we handle this in IBM Tivoli Storage Productivity Center? Use the Filter capability in combination with clever naming conventions for your virtual disks.
How can we be clever when we are limited to only 15 characters? Ok. We understand.
We are currently using an SSPC with Windows 2003 and 2GB memory, but we are only using the Productivity Center for Replication feature of it. Can we move the DB2 database over to a Windows 2008 server with 4GB of memory?
Consider using the IBM Tivoli Storage Productivity Center for Replication software instead of SSPC for special
circumstances like this.
We love the XIV GUI, how soon will all other IBM storage products have it also? As with every acquisition,
IBM evaluates if there are technologies from new products that can be carried back to existing products.
We are currently using 12 ports on our existing XIV, and love it so much we plan to buy a second frame, but are concerned about consuming another 12 ports on our SAN switch. Any suggestions? Yes, use only six ports per frame. Just because you have more ports, doesn't mean you are required to use them.
We have heard there are concerns from the legal community about using deduplication technology, any ideas how to address that?
Nobody here in the room is a lawyer, and you should consult legal counsel for any particular situation.
None of the IBM offerings intended for non-erasable, non-rewriteable (NENR) data retention records (DR550, WORM tape, N series SnapLock) support dedupe today, and none of IBM's deduplication offerings (TS7650,N series A-SIS,TSM) make any claims for fit-for-purpose for compliance regulatory storage. However, be assured that all of IBM's dedupe technology involves byte-for-byte comparisons so that you never lose any data due to false hash collisions. For all IBM compliance storage, what you write will be read back in the correct sequence of ones and zeros.
Continuing my week in Chicago for the IBM Storage and Storage Networking Symposium and System x and BladeCenter Technical Conference, I presented a variety of topics.
Hybrid Storage for a Green Data Center
The cost of power and cooling has risen to be a #1 concern among data centers. I presented the following hybrid storage solutions that combine disk with tape. These provide the best of both worlds, the high performance access time of disk with the lower costs and reduced energy consumption of tape.
IBM [System Storage DR550] - IBM's Non-erasable, Non-rewriteable (NENR) storage for archive and compliance data retention
IBM Grid Medical Archive Solution [GMAS] - IBM's multi-site grid storage for PACS applications and electronic medical records[EMR]
IBM Scale-out File Services [SoFS] - IBM's scalable NAS solution that combines a global name space with a clustered GPFS file system, serving as the ideal basis for IBM's own[Cloud Computing and Storage] offerings
Not only do these help reduce energy costs, they provide an overall lower total cost of ownership (TCO) thantraditional WORM optical or disk-only storage configurations.
The Convergence of Networks - Understanding SAN, NAS and iSCSI in the Data Center Network
This turned out to be my most popular session. Many companies are at a crossroads in choosing data and storage networking solutions in light of recent announcements from IBM and others. In the span of 75 minutes, I covered:
Block storage concepts, storage virtualization and RAID levels
File system concepts, how file systems map files to block storage
Network Attach Storage, the history of the NFS and CIFS protocols, Pros and Cons of using NAS
Storage Area Networks, the history of SAN protocols including ESCON, FICON and FCP, Pros and Cons of using SAN
IP SAN technologies, iSCSI and Fibre Channel over Ethernet (FCoE), Pros and Cons of using this approach
Network Convergence with Infiniband and Fibre Channel over Convergence Enhanced Ethernet (FCoCEE), why Infiniband was not adopted historically in the marketplace as a storage protocol, and the features and enhancements of Convergence Enhanced Ethernet (CEE) needed to merge NAS, SAN and iSCSI traffic onto a single converged data center network [DCN]
Yes, it was a lot of information to cover, but I managed to get it done on time.
IBM Tivoli Storage Productivity Center version 4.1 Overview and Update
In conferences like these, there are two types of product-level presentations. An "Overview" explains howproducts work today to those who are not familiar with it. An "Update" explains what's new in this version of the product for those who are already familiar with previous releases. I decided to combine these into one sessionfor IBM's new version of [Tivoli Storage Productivity Center].I was one of the original lead architects of this product many years ago, and was able to share many personalexperiences about its evolution in development and in the field at client facilities.Analysts have repeatedly rated IBM Productivity Center as one of the top Storage Resource Management (SRM) tools available in the marketplace.
Information Lifecycle Management (ILM) Overview
Can you believe I have been doing ILM since 1986? I was the lead architect for DFSMS which provides ILM support for z/OS mainframes. In 2003-2005, I spent 18 months in the field performingILM assessments for clients, and now there are dozens of IBM practitioners in Global Technology Services andSTG Lab Services that do this full time. This is a topic I cover frequently at the IBM Executive Briefing Center[EBC], because it addressesseveral top business challenges:
Reducing costs and simplifying management
Improving efficiency of personnel and application workloads
Managing risks and regulatory compliance
IBM has a solution based on five "entry points". The advantage of this approach is that it allows our consultants to craft the right solution to meet the specific requirements of each client situation. These entry points are:
Tiered Information Infrastructure - we don't limit ourselves to just "Tiered Storage" as storage is only part of a complete[information infrastructure] of servers,networks and storage
Storage Optimization and Virtualization - including virtual disk, virtual tape and virtual file solutions
Process Enhancement and Automation - an important part of ILM are the policies and procedures, such as IT Infrastructure Library [ITIL] best practices
Archive and Retention - space management and data retention solutions for email, database and file systems
I did not get as many attendees as I had hoped for this last one, as I was competing head-to-head in the same time slot as Lee La Frese covering IBM's DS8000 performance with Solid State Disk (SSD) drives, John Sing covering Cloud Computing and Storage with SoFS, and Eric Kern covering IBM Cloudburst.
I am glad that I was able to make all of my presentations at the beginning of the week, so that I can then sit back and enjoy the rest of the sessions as a pure attendee.
Last week, I was in Austin, and had dinner at [Rudy's Country Store and BBQ]. They offer their self-proclaimed "Worst BBQ in Austin!" with brisket, sausage and other meats by weight. I got a beer, some potato salad, and creamed corn, all at additional cost, of course. When I went to the cashier to pay, I was offered all the white bread I wanted at no additional charge. Are you kidding me? You are going to charge me for beer, but give me 8 to 12 complimentary slices of white bread (practically half a loaf)? Honestly, I consider bread and beer to be basically the same functional food item, differing only in solid versus liquid form. I chose to have only four slices. The food was awesome!
I am reminded of that from my latest exchange with EMC.It didn't take long after IBM's announcement yesterday of IBM's continued investment in its strategic product set, IBM System Storage DS8000 series, that competitors responded. In particular, fellow blogger BarryB from EMC has a post [DS8000 Finally Gets Thin Provisioning] that pokes fun at the new Thin Provisioning feature.
Interestingly, the attack is not on the technical implementation, which is straightforward and rock-solid, but rather that the feature is charged at a flat rate of $69,000 US dollars (list price) per disk array. BarryB claims that recently EMC Corporate has decided to reduce the price of their own thin provisioning, called Symmetrix Virtual Provisioning (VP) on select subset of models of their storage portfolio, although I have not found an EMC press release to confirm. In other words, EMC will bury the cost of thin provisioning into the total cost for new sales, and stop shafting, er.. over-charging their existing Symmetrix customers that are interesting in licensing this feature.
BarryB claims this was a lucky coincidence that his blog post happened just days before IBM's announcement.
(Update: While the timing appears suspicious, I am not accusing Mr. Burke in anywrongdoing of insider information of IBM's plans, nor am I aware of any investigations on this matter from the SEC or any other government agency, and apologize if my previous attempt at humor suggested otherwise. BarryB claimsthat the reduction in price was motivated to counter publicly announced HDS's "Switch In On" program, that it is not a secret thatEMC reduced VP pricing weeks ago, effective beginning 3Q09, just not widely advertised in any formal EMC press releases.Perhaps this new VP pricing was only disclosed to just EMC's existing Symmetrix customers, Business Partners, and employees. Perhaps EMC's decision not to announce this in a Press Release was to avoid upsetting all the EMC CLARiiON customers that continue to pay for Thin Provisioning, or to avoid a long line of existing VP customers asking for refunds. In any case, people are innocent until proven otherwise, and BarryB rightfully deserves the presumption of innocence in this regard. I'm sorry, BarryB, for any trouble my previous comments may have caused you.)
Instead, let's explore some events over the past year that have led up to this.
Let's start with what EMC previously charged for this feature. Software features like this often follow a common pricing method, based per TB, so larger configurations pay more, but tiered in a manner that larger configurations pay less per TB, combined with a yearly maintenance cost.
(Updated: EMC has asked me nicely not to post their actual list prices,so I will provide rough estimates instead. According to BarryB, these are no longer the current prices, soI present them as historical figures for comparison purposes only.)
Initial List price
Software Maintenance (SWMA) percentage
Software Maintenance per year
Number of years
Software License Cost (4 years)
Holy cow! How did EMC get away charging so much for this? To be fair, these are often deeply discounted, a practice common among the industry. However, it was easy for IBMers to show EMC customers that putting SVC or N series gateways in front of their existing EMC disks was more cost effective. Both SVC and N series, as well as IBM's XIV, provide thin provisioning at no additional charge.
HDS offers their own thin provisioning called Hitachi Dynamic Provisioning.Hitachi also offers an SVC-like capability to virtualize storage behind the USP-V. However, I suspect thatfewer than 10 percent of their install base actually licensed this capability because it cost so much. Under the cost pressure from IBM's thin provisioning capabilities in SVC, XIV and N series, Hitachi launched its ["Switch It On"] marketing campaign to activate virtualization and provide some features at no additional charge, including the first 10TB of Hitachi Dynamic Provisioning.
Last week, Martin Glassborow on his StorageBod blog, argued that EMC and HDS should[Set the Wide Stripes Free]. Here is an excerpt:
HDS and EMC are both extremely guilty in this regard, both Virtual Provisioning and Dynamic Provisioning cost me extra as an end-user to license. But this is the technology upon which all future block-based storage arrays will be built. If you guys want to improve the TCO and show that you are serious about reducing the complexity to manage your arrays, you will license for free. You will encourage the end-user to break free from the shackles of complexity and you will improve the image of Tier-1 storage in the enterprise.
Martin is using the term "free" in two contexts above. In the Linux community, we are careful to clarify "free, as in free speech" or "free, as in free beer". Technically, EMC's virtual provisioning is neither, as one has to purchase the hardware to get the feature, so the term "at no additional charge" is more legally correct.
However, the discussion of "free beer" brings me back to my first paragraph about Rudy's BBQ. Nearly everyone eats bread, with the exception of those with [Celiac Disease] that causesan intolerance for gluten protein in wheat, so burying the cost of white bread in the base cost of the BBQ meat is reasonable. In contrast, not everyone drinks beer, and there are probably several people whowould complain if the cost of beer was included in the cost of the BBQ meat, so charging separately forbeer makes business sense.
The same applies in the storage industry. When all (or most) customers of a product can benefit from a feature, it makes sense to include it at no additional charge. When a significant subset might not want to pay a higher base price because they won't use or benefit from a feature, it makes sense to make it optionally priced.
For the IBM SVC, XIV and N series, all customers can benefit from thin provisioning, so it is included at no additional charge.
For the IBM System Storage DS8000, perhaps some 30 to 40 percent of our clients have only System z and/or System i servers attached, and therefore would not benefit from this new thin provisioning. It may seem unfair to raise the price on everybody. The $69,000 flat rate was competitively priced against the prices EMC, HDS and 3PAR were charging for similar capability, and lower than the cost to add a new SVC cluster in front of the DS8000. IBM also charges an annual maintenance, but far lower than what others charged as well.
(Note: These list prices are approximate, and vary slightly based on whether you are on legacy, ESA, Servicesuite or ServiceElect software and subscription (S&S) service plans, and the machine type/model. The tables were too complicated to include here in this post, so these numbers are rounded for comparison purposes only.)
IBM flat rate
Software Maintenance per year (approx)
Number of years
Software License Cost (4 years)
Pricing is more art than science. Getting the right pricing structure that appears fair to everyone involved can be a complicated process.
Well, it's Tuesday, and you know what that means? IBM announcements!
Today we had several for the IBM System Storage product line. Here are some of them:
DS8000 gets thinner, leaner and faster
The 4.3 level of microcode for the IBM System Storage DS8000 series disk systems [announced enhancements] for both fixed block architecture (FBA) LUNs and count key data (CKD) volumes.
For FBA LUNs that attach to Linux, UNIX and Windows distributed systems, IBM announced DS8000 Thin Provisioning native support. Of course, many people already had this by putting IBM System Storage SAN Volume Controller (SVC) in front, but now DS8000 clients out there without SVC can also achieve benefits ofthin provisioning. This support also improves quick initialization a whopping 2.6 times faster.
For CKD volumes attached to z/OS on System z mainframes, IBM announced zHPF multitrack support for z/OS 1.9 and above. zHPF provide high performance FICON performance, and can now handle multitrack I/O transfers foreven better performance for zFS, HFS, PDSE, and extended striped data sets.
XIV gets better connected
A lot of XIV[announced enhancements] and preview announcements centered around better connectivity. Here's a run down:
Better host attachment connectivity by beefing up the interface modules that hold the FCP and iSCSI interface cards. XIV disk arrays have 3 to 6 of these in different configurations, and since they manage both their own disks,as well as receive host I/O requests for other disks, are basically doing double-duty.These interface modules can now be ordered as [Dual-CPU] modules.
Better infrastructure management by connecting XIV with the industry standard SMI-S interface to IBM Tivoli Storage Productivity Center. Now, XIV can be part of the single pane of glass console that manages all of your other disk arrays, tape libraries and SAN fabrics.
Better copy services for backups by connecting XIV with IBM Tivoli Storage Manager Advanced Copy Services. TSM for Advanced Copy Services is application aware and can coordinate XIV Snapshots similar to its current support for SVC and DS8000 FlashCopy capabilities.
Better connectivity to security systems by supporting LDAP credentials. Before, you had individual userid and passwords for each XIV, and these were probably different than all the other userid/password combinations you have for every other box on your data center floor. IBM is working on getting all products to support theLightweight Directory Access Protocol, or [LDAP] so that we can reach the nirvana of "single sign-on",one userid/password per administrator for all IT devices in the company.
Better support with flexible warranty periods and non-disruptive code load options.
Better remote copy support by connecting to sites far, far away. IBM previewed that it will provideasynchronous disk mirroring from one XIV to another XIV natively. Before this, XIV's synchronous mirroring was limited to 300km distances. Many of our clients do long distance global mirroring of their XIV today behind an SVC, but again, for those out there that don't yet have an SVC, this can be a reasonable alternative.
TS7650 ProtecTIER data deduplication appliance now offers "no dedupe" option
In what some might consider a surprising move, IBM announced a "no dedupe" licensing option on their premiere deduplication solution, which somewhat reminds me of IBM's NOCOPY option on DS8000 FlashCopy. At first I thought "Are you kidding me?!?!" However, this new license option allows the TS7650 appliance to compete with other virtual tape libraries (VTL) that do not offer deduplication capability on an even playing field. It also allows TS7650 to be used for data that doesn'tdedupe very well, such as seismic recordings, satellite images, or what have you. There are also clients who do not yet feel comfortable to dedupe their financial records for compliance reasons.This option now allows IBM to withdraw from marketing the TS7530 non-dedupe library. Having one technology thatdoes both dedupe and no-dedupe is better than offering two separate libraries based on different technologies.
The ProtecTIER series also announced [IP remote distance replication]. This can be used to replicate virtualtape cartridges in one ProtecTIER over to another ProtecTIER at a remote location. You can decide to replicateall or just a subset of your virtual tapes, and this feature can be used to migrate, merge or split ProtecTIERconfigurations as your needs grow. Before this support, our TS7650G clients replicated the disk repositoryusing native disk array replication technology, such as Global Mirror on the DS8000, but that meant that all data was replicated over to the secondary site. Now, with this new IP replication feature, you can be selective, and replicate only those virtual tapes that are mission critical.
The appliance now supports up to 36TB of disk capacity, and the new "IBM i" operating system on System i servers,formerly known as i5/OS.
GPFS does Windows
IBM's General Parallel File System (GPFS) has the lion's marketshare of file systems used in the [Top 500 Supercomputers]. For a while, it was limited to just Linux and AIX operating system support, but version 3.3 [extends this to Windows 2008 on 64-bit architectures]. GPFS isthe file system used in IBM's Scale-Out File Services, the underlying technology of IBM's Cloud Computing and Storage offerings.
Well, I am back from Las Vegas, and had a pleasant [US Memorial Day] holiday yesterday.
Today is Tuesday, and that means more IBM announcements! IBM announced that the DCS9900 now supports an intermix of SAS and SATA drives. The DCS9900 is purpose-built specifically for the High-Performance-Computing (HPC) and Video Broadcasting industries.
The system is a combination of 4U controllers and 3U expansion drawers. The controllers handle either FC or Infiniband attachment to host servers. The expansion drawers hold up to 60 drives each. With the new features of intermix, the following drives are supported:
7200 RPM SATA drives in 500, 750 and 1000 GB capacities
15K RPM SAS drives in 146, 300 and 450 GB capacities
The DCS9900 groups the drives into sets of 10, in RAID-6 ranks of 8+2P. IBM supports either 5, 10 or 20 expansion drawers to make a complete system. The maximum configuration would be 1200 drives of the 1000GB SATA drives, for a total of 1.2 PB in two frames. Each rank must be all the same type and capacity drive, but you can mix different types within the entire system.
The DCS9900 supports "Sleep Mode", an implementation of Massive Array of Idle Disks [MAID] technology, whereby each RAID rank can be either awake and spinning, or in energy-efficient standby mode. This makes for a more "green" storage system for data that is not accessed frequently.
Continuing my ongoing discussion on Solid State Disk (SSD), fellow blogger BarryB (EMC) points out in his [latest post]:
Oh – and for the record TonyP, I don't think I ever said EMC was using a newer or different EFDs than IBM. I just asserted that EMC knows more than IBM about these EFDs and how they actually work a storage array under real-world workloads.
(Here "EFD" is refers to "Enterprise Flash Drive", EMC's marketing term for Single Layer Cell (SLC) NAND Flash non-volatile solid-state storage devices. Both IBM and EMC have been selling solid-state storage for quite some time now, but EMC felt that a new term was required to distinguish the SLC NAND Flash devices sold in their disk systems from solid-state devices sold in laptops or blade servers. The rest of the industry, including IBM, continues to use the term SSD to refer to these same SLC NAND Flash devices that EMC is referring to.)
Although STEC asserts that IBM is using the latest ZeusIOPS drives, IBM is only offering the 73GB and 146GB STEC drives (EMC is shipping the latest ZeusIOPS drives in 200GB and 400GB capacities for DMX4 and V-Max, affording customers a lower $/GB, higher density and lower power/footprint per usable GB.)
Here is where I enjoy the subtleties between marketing and engineering. Does the above seem like he is saying EMC is using newer or different drives? What are typical readers expected to infer from the statement above?
That there are four different drives from STEC, in four different capacities. In the HDD world, drives of different capacities are often different, and larger capacities are often newer than those of smaller capacities.
That the 200GB and 400GB are the latest drives, and that 73GB and 146GB drives are not the latest.
That STEC press release is making false or misleading claims.
Uncontested, some readers might infer the above and come to the wrong conclusions. I made an effort to set the record straight. I'll summarize with a simple table:
Usable (conservative format)
Usable (aggressive format)
So, we all agree now that the 256GB drives that are formatted as 146GB or 200GB are in fact the same drives, that IBM and EMC both sell the latest drives offered by STEC, and that the STEC press release was in fact correct in its claims.
I also wanted to emphasize that IBM chose the more conservative format on purpose. BarryB [did the math himself] and proved my key points:
Under some write-intensive workloads, an aggressive format may not last the full five years. (But don't worry, BarryB assures us that EMC monitors these drives and replaces them when they fail within the five years under their warranty program.)
Conservative formats with double the spare capacity happen to have roughly double the life expectancy.
I agree with BarryB that an aggressive format can offer a lower $/GB than the conservative format. Cost-conscious consumers often look for less-expensive alternatives, and are often willing to accept less-reliable or shorter life expectancy as a trade-off. However, "cost-conscious" is not the typical EMC targeted customer, who often pay a premiumfor the EMC label. To compensate, EMC offers RAID-6 and RAID-10 configurations to provide added protection. With a conservative format, RAID-5 provides sufficient protection.
(Just so BarryB won't accuse me of not doing my own math, a 7+P RAID-5 using conservative format 146GB drives would provide 1022GB of capacity, versus 4+4 RAID-10 configuration using aggressive format 200GB drives only 800GB total.)
In an ideal world, you the consumer would know exactly how many IOPS your application will generate over the next five years, exactly how much capacity you will require, be offered all three drives in either format to choose from, and make a smart business decision. Nothing, however, is ever this simple in IT.