My post last week [Solid State Disk on DS8000 Disk Systems
] kicked up some dust in the comment section.Fellow blogger BarryB (a member of the elite [Anti-Social Media gang from EMC
]) tried to imply that 200GB solid state disk (SSD) drives were different or better than the 146GB drives used in IBM System Storage DS8000 disk systems. I pointed out that they are the actual same physical drive, just formatted differently.
To explain the difference, I will first have to go back to regular spinning Hard Disk Drives (HDD). There are variances in manufacturing, so how do you make sure that a spinning disk has AT LEAST the amount of space you are selling it as? The solution is to include extra. This is the same way that rice, flour, and a variety of other commodities are sold. Legally, if it says you are buying a pound or kilo of flour, then it must be AT LEAST that much to be legal labeling. Including some extra is a safe way to comply with the law. In the case of disk capacity, having some spare capacity and the means to use it follows the same general concept.
(Disk capacity is measured in multiples of 1000, in this case a Gigabyte (GB) = 1,000,000,000 bytes, not to be confused with [Gibibyte (GiB)] = 1,073,741,824 bytes, based on multiples of 1024.)
Let's say a manufacturer plans to sell 146GB HDD. We know that in some cases there might be bad sectors on the disk that won't accept written data on day 1, and there are other marginally-bad sectors that might fail to accept written data a few years later, after wear and tear. A manufacturer might design a 156GB drive with 10GB of spare capacity and format this with a defective-sector table that redirects reads/writes of known bad sectors to good ones. When a bad sector is discovered, it is added to the table, and a new sector is assigned out of the spare capacity.Over time, the amount of space that a drive can store diminishes year after year, and once it drops below its rated capacity, it fails to meet its legal requirements. Based on averages of manufacturing runs and material variances, these could then be sold as 146GB drives, with a life expectancy of 3-5 years.
With Solid State Disk, the technology requires a lot of tricks and techniques to stay above the rated capacity. For example, you can format a 256GB drive as a conservative 146GB usable, with an additional 110GB (75 percent) spare capacity to handle all of the wear-leveling. You could lose up to 22GB of cells per year, and still have the rated capacity for the full five-year life expectancy.
Alternatively, you could take a more aggressive format, say 200GB usable, with only 56GB (28 percent) of spare capacity. If you lost 22GB of cells per year, then sometime during the third year, hopefully under warranty, your vendor could replace the drive with a fresh new one, and it should last the rest of the five year time frame. The failed drive, having 190GB or so usable capacity, could then be re-issued legally as a refurbished 146GB drive to someone else.
The wear and tear on SSD happens mostly during erase-write cycles, so for read-intensive workloads, such as boot disks for operating system images, the aggressive 200GB format might be fine, and might last the full five years.For traditional business applications (70 percent read, 30 percent write) or more write-intensive workloads, IBM feels the more conservative 146GB format is a safer bet.
This should be of no surprise to anyone. When it comes to the safety, security and integrity of our client's data, IBM has always emphasized the conservative approach.[Read More]
Looks like fellow blogger and arch nemesis BarryB from EMC is once again stirring up trouble, this time he focuses his attention on IBM's leadership in Solid State Disk (SSD) on the IBM System Storage DS8000 disk systems in his post [IBM's amazing splash dance, part deux
], a follow-up to [IBM's amazing splash dance
] and multi-vendor tirade [don't miss the amazing vendor flash dance
(Note: IBM [Guidelines] prevent me from picking blogfights, so this post is only to set the record straight on some misunderstandings, point to some positive press about IBM's leadership in this area, and for me to provide a different point of view.)
First, let's set the record straight on a few things. The [RedPaper is still in draft form] under review, and so some information has not yet been updated to reflect the current situation.
- You can have 16 or 32 SSD per DA pair. However, you can only have a maximum of 128 SSD drives total in any DS8100 or DS8300. In the case of the IBM DS8300 with 8 DA pairs, it makes more senseto spread the SSD out across all 8 pairs, and perhaps this is what confused BarryB.
- Yes, you can order an all-SSD model of the IBM DS8000 disk system. I don't see anywhere in the RedPaper that suggests otherwise, and I have confirmed with our offering manager that this is the case.
- The 73GB and 146GB are freshly manufactured from STEC. The 146GB drive and 200GB drives are actually the same drive but just formatted differently. The 200GB format does not offer as much spare capacity for wear-leveling, and are therefore intended only for read-intensive workloads. (Perhaps EMC wants you to find this out the hard way so that you replace them more often???) These reduced-spare-capacity formats may not be appropriate with some write-intensive workloads. Don't let anyone from EMC try to misrepresent the 73GB or 146GB drives from STEC as older, obsolete, collecting dust in a warehouse, or otherwise no longer manufactured by STEC.
- You can relocate data from HDD to SSD using "Data Set FlashCopy", a feature that does not involve host-based copy services, does not consume any MIPS on your System z mainframe, and is performed inside the DS8000 disk system. You can also use host-based copy services as well, but it is not the only way.
- You can use any supported level of z/OS with SSD in the IBM DS8000. There is ENHANCED support mentioned in the RedPaper that you get only with z/OS 1.8 and above, allowing you to create automation policies that place data sets onto SSD or non-SSD storage pools. This synergy makes SSD with IBM DS8000 superior to the initial offerings that EMC had offered without this OS support.
I find it amusing that BarryB's basic argument is that IBM's initial release of SSD disk on DS8000 is less than what the potential architecture could be extended to support much more. Actually, if you look at EMC's November release of Atmos, as well as their most recent announcement of V-Max, they basically say the same thing "Stay Tuned, this is just our initial release, with various restrictions and limitations, but more will follow." Architecturally, IBM DS8000 could support a mix of SSD and non-SSD on the same DA pairs, could support RAID6 and RAID10 as well, and could support larger capacity drives or use higher-capacity read-intensive formats. These could all be done via RPQ if needed, or in a follow-on release.
BarryB's second argument is that IBM is somehow "throwing cold water" on SSD technology. That somehow IBM is trying to discourage people from using SSD by offering disk systems with this technology. IBM offered SSD storage on BladeCenter servers LONG BEFORE any EMC disk system offering, and IBM continues to innovate in ways that allow the best business value of this new technology. Take for example this 24-page IBM Technical Brief:[IBM System z® and System Storage DS8000:Accelerating the SAP® Deposits Management Workload With Solid State Drives]. It is full of example configurations that show that SSD on IBM DS8000 can help in practical business applications. IBM takes a solution view, and worked with DB2, DFSMS, z/OS, High Performance FICON (zHPF), and down the stack to optimize performance to provide real business value innovation. Thanks to this synergy,IBM can provide 90 percent of the performance improvement with only 10 percent of the SSD disk capacity as EMC offerings. Now that's innovative!
The price and performance differences between FC and SATA (what EMC was mostly used to) is only 30-50 percent. But the price and performance differences between SSD and HDD is more than an order of magnitude in some cases 10-30x, similar to the differences between HDD and tape. Of course, if you want hybrid solutions that take best advantage of SSD+HDD, it makes more sense to go to IBM, the leading storage vendor that has been doing HDD+Tape hybrid solutions for the past 30 years. IBM understands this better, and has more experience dealing with these orders of magnitude than EMC.
But don't just take my word for it. Here is an excerpt from Jim Handy, from [Objective Analysis] market research firm, in a recent Weekly Review from [Pund-IT] (Volume 5, Issue 23--May 6, 2009):
"What about IBM? One thing that we are finding is that IBM really “Gets It” in the area offlash in the data center. Readers of the Pund-IT Review will not only recall that IBM Researchpushed its SSD-based “Quicksilver” storage system to one million IOPS using Fusion-ioflash-based storage, but they also may have noticed that the recent MySQL and mem-cachedappliances recently introduced by Schooner Information Technology are both flash-enableddevices introduced in partnership with IBM. Ironically, while other OEMs are takingthe cautious approach of introducing a standard SSD option to their systems first, IBM appearsto have been working on several approaches simultaneously to bring flash to thedata center not only in SSDs, but in innovative ways as well."
As for why STEC put out a press release on their own this week without a corresponding IBM press release, I can only say that IBM already announced all of this support back in February, and I blogged about it in my post [Dynamic Infrastructure - Disk Announcements 1Q09]. This is not the first time one of IBM's suppliers has tried to drum up business in this manner. Intel often funds promotions for IBM System x servers (the leading Intel-based servers in the industry) to help drive more business for their Xeon processor.
So, BarryB, perhaps its time for you to take out your green pen and work up another one of your all-too-common retraction and corrections.[Read More]
It's Tuesday, which means IBM announcements, and today IBM made some major announcementsthat support a [Dynamic Infrastructure
]! I hinted at this yesterday, choosing the week's theme to be all about Cloud Computing and Alternative Sourcing. I will briefly highlight today's announcements related to storage here, and try to go into more detail over the next few weeks.
- Ethernet switches and routers
In support of Cloud Computing and Cloud Storage, IBM is now back in theEthernet networking business. This is part of storage as protocols likeiSCSI, CIFS and NFS are gaining prominence. Extending IBM's existing OEMrelationship with Brocade, there are four series:
- [c-series] - "c" for Compact, these are 1U high fixed port switches
- [g-series] - "g" for Pay-as-you-Grow using IronStack stacking technology to allow up to 8 switches to be
glommed, glued, er.. "gathered" together as a single virtual chassis.
- [m-series] - "m" for Multiprotocol Label Switching [MPLS] which supports routing between LAN and WAN networks over OC12 and OC48 lines.
- [s-series] - "s" for slots, the B08S has eight slots, and the B16S has sixteen slots, supporting up to 384 ports. These models support Power-over-Ethernet [PoE] that simplifies attaching Voice-over-IP (VoIP) telephones and IP-based surveillance cameras.
IBM announced it will strengthen its partnership with Juniper Networks, and continues to consider Cisco a strategic partner as well. To help customer position themselves for Cloud Computing and Cloud Storage,IBM also launches some new services:
- IBM System Storage DS5000 disk system
The IBM [DS5000] now supports self-encrypting disk drives, known also as "full-disk encryption" or FDE, for added security, and 8Gbps Fibre Channel (FC) ports for added performance. The DS5300 model in particular now supports up to 448 disk drives for added scalability.
- Comprehensive Data Protection Solution
IBM's [Data Protection Solution] shows off IBM's awesome synergy between servers, storage and software. Combining System x servers, Tivoli Storage Manager FastBack software, and DS5000, DS4000 or DS3000 series disk systems. The solution is designed to both Windows-based servers and their applications, offering bare metal restores, and application–level protection for Oracle, SQL, Exchange and SAP.
- Tivoli Storage Productivity Center
Last February, IBM previewed the renaming of TotalStorage Productivity Center to its new name,Tivoli Storage Productivity Center. Today, IBM announces [Tivoli Storage Productivity Center v4.1]. Some key changes include:
- Productivity Center for Fabric has been merged into Productivity Center for Disk
- Productivity Center for Replication is now integrated, but remains separately licensed
- Productivity Center can now feed input to IBM's Novus Storage Enterprise Resource Planner [SERP]
- TS7650 ProtecTIER Data Deduplication IP-based replication
IBM previews IP-based replication which allows the TS7650 appliance or TS7650G gateway to sendvirtual tape data over to a remote location. This is instead of having the underlying disk systemsperform the replication on its behalf. Having the TS7650 do the replication is preferred, as itcan maintain virtual cartridge integrity, when a virtual tape is unmounted the replication can beginat that point.
This is just a small subset of all the announcements. For more information, see this 28-pagepresentation [Manage the Explosion of Information with IBM Information Infrastructure].
technorati tags: IBM, Dynamic Infrastructure, Ethernet, switches, routers, Cloud Computing, Cloud Storage, Brocade, Juniper Networks, Cisco, IronStack, FCoE, FCoCEE, PoE, DS5000, FC, FDE, TSM, FastBack, TotalStorage, Tivoli, Storage, Productivity Center, Novus, SERP, TS7650, TS77650G, ProtecTIER, Information Infrastructure
Earlier this week, EMC announced its Symmetrix V-Max, following two trends in the industry:
- Using Roman numerals. The "V" here is for FIVE, as this is the successor to the DMX-3 and DMX-4. EMC might have gotten the idea from IBM's success with the XIV (which does refer to the number 14, specifically the 14th class of a Talpiot program in Israel that the founders of XIV graduated from).
- Adding "-Max", "-Monkey" or "2.0" at the end of things to make them sound more cool and to appeal to a younger, hipper audience. EMC might have gotten this idea from Pepsi-Max (... a taste of storage for the next generation?)
I took a cue from President Obama and waited a few days to collect my thoughts and do my homework before responding.Special thanks to fellow blogger ChuckH in giving me a [handy list of reactions] for me to pick and choose from. It appears that EMC marketing machine feels it is acceptable for their own folks to claim that EMC is doing something first, or that others are catching up to EMC, but when other vendors do likewise, then that is just pathetic or incoherent. Here are a few reactions already from fellow bloggers:
This was a major announcement for EMC, addressing many of the problems, flaws and weaknesses of the earlier DMX-3 and DMX-4 deliverables. Here's my read on this:
- More ports
Now you can have as many FCP ports (128) as an IBM System Storage DS8300, although the maximum number of FICON ports is still short, and no mention of ESCON support. The Ethernet ports appear to be 1Gb, not the new 10GbE you might expect.
- Support for System z mainframe
V-Max adds some new support to catch up with the DS8000, like Extended Address Volumes (EAV). EMC is still not quite there yet. IBM DS8000 continues to be the best, most feature-rich storage option if you have System z mainframe servers.
- Improved Performance
Both the IBM DS8000 and HDS USP-V beat the DMX-4 in performance, and in some cases the DMX-4 even lost to the IBM XIV, so EMC had to do something about it. EMC chooses not to participate in industry-standard performance benchmarks like those from the [Storage Performance Council], which limits them to vague comparisons against older EMC gear. I'll give EMC engineers the benefit of the doubt and say that now V-Max is now "comparably as fast as HDS and IBM offerings".
- Getting "V" in the name
The "V" appears to be for the roman number five, not to be confused with external heterogeneous storage virtualization that HDS USP-V and IBM SVC provide. There is no mention of synergy with EMC's failed "Invista" product, and I see no support for attaching other vendors disk to the back of this thing.
- Switch to Intel processor
Apple switched its computers from PowerPC to Intel-based, and now EMC follows in the same path. There are some custom ASICs still in V-Max, so it is not as pure as IBM's offerings.
- Modular, XIV-like Scale-out Architecture
Actually, the packaging appears to follow the familiar system bays and storage bays of the DMX-4 and DMX-4 950 models, but architecturally offers XIV-like attachment across a common switch network between "engines", EMC's term for interface modules.
- Non-disruptive data migration
IBM's SoFS, DR550 and GMAS have this already, as does as anything connected behind an IBM SAN Volume Controller.
A long time ago, IBM used to have midrange disk storage systems called "FAStT" which stood for Fibre Array Storage Technology, so this might have given EMC the idea for their "Fully Automated Storage Tiering" acronym. The concept appears similar to what IBM introduced back in 2007 for the Scale-Out-File Services [SofS] which not only provides policy-based placement, movement and expiration on different disk tiers, includes tape tiers as well for a complete solution. I don't see anything in the V-Max announcement that it will support tape anytime soon.
And what ever happend to EMC's Atmos? Wasn't that supposed to be EMC's new direction in storage?
- Zero-data loss Three-site replication
IBM already calls this Metro/Global Mirror for its IBM DS8000 series, but EMC chose to call it SRDF/EDP for Extended Distance Protection.
- Ease of Use
The most significant part of the announcement is that EMC is finally focusing on ease-of-use.In addition to reducing the requirement for "Bin File" modifications, this box has a redesigned user interface to focus on usability issues. For past DMX models, EMC customers had to either hire EMC to do tasks for them that were just to difficult otherwise, or buy expensive software like their EMC Control Center to manage. EMC willcontinue to sell DMX-4 boxes for a while, as they are probably supply-constrained on the V-Max side, but I doubt they will retro-fit these new features back to DMX-3 and DMX-4.
When IBM announced its acquisition of XIV over a year ago now, customers were knocking down our doors to get one. This caught two particular groups looking like a [deer in headlights]:
- EMC Symmetrix sales force: Some of the smarter ones left EMC to go sell IBM XIV, leaving EMC short-handed and having to announce they [were hiring during their layoffs]. Obviously, a few of the smart ones stayed behind, to convince their management to build something like the V-Max.
- IBM DS8000 sales force: If clients are not happy with their existing EMC Symmetrix, why don't they just buy an IBM DS8000 instead? What does XIV have that DS8000 doesn't?
Let me contrast this with the situation Microsoft Windows is currently facing.
|I am often asked by friends to help them pick out laptops and personal computers. I use Linux, Windows and MacOS, so have personal experience with all three operating systems.|
Linux is cheaper, offers the power-user the most options for supporting older, less-powerfulequipment, but I wouldn't have my Mom use it. While distributions like Ubuntu are makinggreat strides, it is just too difficult for some people.
MacOS is nice, I like it, it works out of the box with little or no customization and an intuitive interface. However, some of my friends don't make IBM-level salaries, and have to watch their budget.
In their "I'm a PC" campaign, Microsoft is fighting both fronts. Let's examine two commercials:
- In the first commercial, a young eight-year-old puts together a video from pictures oftoy animals and some background music.The message: "Windows is easier to use than Linux!" If they really wanted to send this message, they should have shown senior citizens instead.
- In the second commercial, a young college student is asked to find a laptop with 17 inchscreen, and a variety of other qualifications, for under $1000 US dollars. The only modelat the Apple store below this price had a 13 inch screen, but she finds a Windows-based system that had this size screen and met all the other qualifications. The message: "Windows-based hardware from a variety of competitors are less expensive than hardware from Apple!"
Both Microsoft and Apple charge a premium for ease-of-use.In the storage world, things are completely opposite. Vendors don't charge a premium forease-of-use. In fact, some of the easiest to use are also the least expensive.
- If you just have Windows and Linux, you can get some entry level system likethe IBM DS3000 series, only a few features, and can be set up in six simple steps.
- Next, if you have a more interesting mix of operating systems, Linux, Windows and some flavorsof UNIX like IBM AIX, HP-UX or Sun Solaris, then you might want the features and functionsof more pricier midrange offerings. More options means that configuration and deploymentis more difficult, however.
- Finally, if you are serious Fortune 500 company, running your mission critical applications on System z or System i centralized systems in a big data center, that you might be willing to pay top dollar for the most feature-rich offerings of an Enterprise-class machine.Thankfully you have an army of highly-trained staff to handle the highest levels of complexity.
IBM's DS8000, HDS USP-V and EMC's Symmetrix are the key players in the Enterprise-classspace. They tried to be ["all things to all people"], er.. perhaps all things to allplatforms. All of the features and functions came at a price, not just in dollars, butin complexity and difficulty. You needed highly skilled storage admins using expensive storage management software, or be willing to hirethe storage vendor's premium services to get the job done.
Alan Cooper wrote a book that would change that mindset, titled[The Inmates Are Running the Asylum: Why High-Tech Products Drive Us Crazy and How to Restore the Sanity]. This book showed why the situation had gotten out ofhand, and to demand better ease-of-use from all vendors. It was required reading for anyone working in or with IBM's "User Centered Design" teams.I highly recommend this book.
IBM recognized this trend early. IBM's SVC, N series and now XIV all offer ease-of-use withenterprise-class features and functions, at lower total cost of ownership than traditional enterprise-class systems. IBM is not the only one, of course, as smaller storage start-ups like 3PAR,Pillar Data Systems, Compellent, and to some extent Dell's EqualLogic all recognized thisand developed clever offerings as well.
While IBM's XIV may not have been the first to introduce a modular, scale-out architectureusing commodity parts managed by sophisticated ease-of-use interfaces, its success might have been the kick-in-the-butt EMC needed to follow the rest of the industry in this direction.
technorati tags: IBM, DS8000, XIV, SVC, EMC, Symmetrix, V-Max, DMX-3, DMX-4, Chuck Hollis, HDS, USP-V, FCP, FICON, ESCON, storage+virtualization, FAStT
Continuing this week's series on Pulse 2009 video, we have a double header. Bob Dalton discusses our entry-level IBM System Storage [DS3000
] and midrange IBM System Storage [DS4000
] disk systems, followed by Dan Thompson discussing [IBM Tivoli Storage Manager FastBack
IBM Tivoli Storage Manager FastBack is the result of IBM's [acquisition of FilesX], a company in Israel that developed software to backup servers at remote branch offices running Microsoft Windows operating system.
technorati tags: IBM, DS3000, DS4000, disk system, Tivoli Storage Manager, TSM, FastBack, FilesX, Israel, Microsoft Windows