Tony Pearson is a Master Inventor and Senior IT Architect for the IBM Storage product line at the
IBM Systems Client Experience 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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Wrapping up my coverage of the annual [2010 System Storage Technical University], I attended what might be perhaps the best session of the conference. Jim Nolting, IBM Semiconductor Manufacturing Engineer, presented the new IBM zEnterprise mainframe, "A New Dimension in Computing", under the Federal track.
The zEnterprises debunks the "one processor fits all" myth. For some I/O-intensive workloads, the mainframe continues to be the most cost-effective platform. However, there are other workloads where a memory-rich Intel or AMD x86 instance might be the best fit, and yet other workloads where the high number of parallel threads of reduced instruction set computing [RISC] such as IBM's POWER7 processor is more cost-effective. The IBM zEnterprise combines all three processor types into a single system, so that you can now run each workload on the processor that is optimized for that workload.
IBM zEnterprise z196 Central Processing Complex (CPC)
Let's start with the new mainframe z196 central processing complex (CPC). Many thought this would be called the z11, but that didn't happen. Basically, the z196 machine has a maximum 96 cores versus z10's 64 core maximum, and each core runs 5.2GHz instead of z10's cores running at 4.7GHz. It is available in air-cooled and water-cooled models. The primary operating system that runs on this is called "z/OS", which when used with its integrated UNIX System Services subsystem, is fully UNIX-certified. The z196 server can also run z/VM, z/VSE, z/TPF and Linux on z, which is just Linux recompiled for the z/Architecture chip set. In my June 2008 post [Yes, Jon, there is a mainframe that can help replace 1500 servers], I mentioned the z10 mainframe had a top speed of nearly 30,000 MIPS (Million Instructions per Second). The new z196 machine can do 50,000 MIPS, a 60 percent increase!
The z196 runs a hypervisor called PR/SM that allows the box to be divided into dozens of logical partitions (LPAR), and the z/VM operating system can also act as a hypervisor running hundreds or thousands of guest OS images. Each core can be assigned a specialty engine "personality": GP for general processor, IFL for z/VM and Linux, zAAP for Java and XML processing, and zIIP for database, communications and remote disk mirroring. Like the z9 and z10, the z196 can attach to external disk and tape storage via ESCON, FICON or FCP protocols, and through NFS via 1GbE and 10GbE Ethernet.
IBM zEnterprise BladeCenter Extension (zBX)
There is a new frame called the zBX that basically holds two IBM BladeCenter chassis, each capable of 14 blades, so total of 28 blades per zBX frame. For now, only select blade servers are supported inside, but IBM plans to expand this to include more as testing continues. The POWER-based blades can run native AIX, IBM's other UNIX operating system, and the x86-based blades can run Linux-x86 workloads, for example. Each of these blade servers can run a single OS natively, or run a hypervisor to have multiple guest OS images. IBM plans to look into running other POWER and x86-based operating systems in the future.
If you are already familiar with IBM's BladeCenter, then you can skip this paragraph. Basically, you have a chassis that holds 14 blades connected to a "mid-plane". On the back of the chassis, you have hot-swappable modules that snap into the other side of the mid-plane. There are modules for FCP, FCoE and Ethernet connectivity, which allows blades to talk to each other, as well as external storage. BladeCenter Management modules serve as both the service processor as well as the keyboard, video and mouse Local Console Manager (LCM). All of the IBM storage options available to IBM BladeCenter apply to zBX as well.
Besides general purpose blades, IBM will offer "accelerator" blades that will offload work from the z196. For example, let's say an OLAP-style query is issued via SQL to DB2 on z/OS. In the process of parsing the complicated query, it creates a Materialized Query Table (MQT) to temporarily hold some data. This MQT contains just the columnar data required, which can then be transferred to a set of blade servers known as the Smart Analytics Optimizer (SAO), then processes the request and sends the results back. The Smart Analytics Optimizer comes in various sizes, from small (7 blades) to extra large (56 blades, 28 in each of two zBX frames). A 14-blade configuration can hold about 1TB of compressed DB2 data in memory for processing.
IBM zEnterprise Unified Resource Manager
You can have up to eight z196 machines and up to four zBX frames connected together into a monstrously large system. There are two internal networks. The Inter-ensemble data network (IEDN) is a 10GbE that connects all the OS images together, and can be further subdivided into separate virtual LANs (VLAN). The Inter-node management network (INMN) is a 1000 Mbps Base-T Ethernet that connects all the host servers together to be managed under a single pane of glass known as the Unified Resource Manager. It is based on IBM Systems Director.
By integrating service management, the Unified Resource Manager can handle Operations, Energy Management, Hypervisor Management, Virtual Server Lifecycle Management, Platform Performance Management, and Network Management, all from one place.
IBM Rational Developer for System z Unit Test (RDz)
But what about developers and testers, such as those Independent Software Vendors (ISV) that produce mainframe software. How can IBM make their lives easier?
Phil Smith on z/Journal provides a history of [IBM Mainframe Emulation]. Back in 2007, three emulation options were in use in various shops:
Open Mainframe, from Platform Solutions, Inc. (PSI)
FLEX-ES, from Fundamental Software, Inc.
Hercules, which is an open source package
None of these are viable options today. Nobody wanted to pay IBM for its Intellectual Property on the z/Architecture or license the use of the z/OS operating system. To fill the void, IBM put out an officially-supported emulation environment called IBM System z Professional Development Tool (zPDT) available to IBM employees, IBM Business Partners and ISVs that register through IBM Partnerworld. To help out developers and testers who work at clients that run mainframes, IBM now offers IBM Rational Developer for System z Unit Test, which is a modified version of zPDT that can run on a x86-based laptop or shared IBM System x server. Based on the open source [Eclipse IDE], the RDz emulates GP, IFL, zAAP and zIIP engines on a Linux-x86 base. A four-core x86 server can emulate a 3-engine mainframe.
With RDz, a developer can write code, compile and unit test all without consuming any mainframe MIPS. The interface is similar to Rational Application Developer (RAD), and so similar skills, tools and interfaces used to write Java, C/C++ and Fortran code can also be used for JCL, CICS, IMS, COBOL and PL/I on the mainframe. An IBM study ["Benchmarking IDE Efficiency"] found that developers using RDz were 30 percent more productive than using native z/OS ISPF. (I mention the use of RAD in my post [Three Things to do on the IBM Cloud]).
What does this all mean for the IT industry? First, the zEnterprise is perfectly positioned for [three-tier architecture] applications. A typical example could be a client-facing web-server on x86, talking to business logic running on POWER7, which in turn talks to database on z/OS in the z196 mainframe. Second, the zEnterprise is well-positioned for government agencies looking to modernize their operations and significantly reduce costs, corporations looking to consolidate data centers, and service providers looking to deploy public cloud offerings. Third, IBM storage is a great fit for the zEnterprise, with the IBM DS8000 series, XIV, SONAS and Information Archive accessible from both z196 and zBX servers.
Continuing my coverage of the annual [2010 System Storage Technical University], I participated in the storage free-for-all, which is a long-time tradition, started at SHARE User Group conference, and carried forward to other IT conferences. The free-for-all is a Q&A Panel of experts to allow anyone to ask any question. These are sometimes called "Birds of a Feather" (BOF). Last year, they were called "Meet the Experts", one for mainframe storage, and the other for storage attached to distributed systems. This year, we had two: one focused on Tivoli Storage software, and the second to cover storage hardware. This post provides a recap of the Storage Hardware free-for-all.
The emcee for the event was Scott Drummond. The other experts on the panel included Dan Thompson, Carlos Pratt, Jack Arnold, Jim Blue, Scott Schroder, Ed Baker, Mike Wood, Steve Branch, Randy Arseneau, Tony Abete, Jim Fisher, Scott Wein, Rob Wilson, Jason Auvenshine, Dave Canan, Al Watson, and myself, yours truly, Tony Pearson.
What can I do to improve performance on my DS8100 disk system? It is running a mix of sequential batch processing and my medical application (EPIC). I have 16GB of cache and everything is formatted as RAID-5.
We are familiar with EPIC. It does not "play well with others", so IBM recommends you consider dedicating resources for just the EPIC data. Also consider RAID-10 instead for the EPIC data.
How do I evaluate IBM storage solutions in regards to [PCI-DSS] requirements.
Well, we are not lawyers, and some aspects of the PCI-DSS requirements are outside the storage realm. In March 2010, IBM was named ["Best Security Company"] by SC Magazine, and we have secure storage solutions for both disk and tape systems. IBM DS8000 and DS5000 series offer Full Disk Encryption (FDE) disk drives. IBM LTO-4/LTO-5 and TS1120/TS1130 tape drives meet FIPS requirements for encryption. We will provide you contact information on an encryption expert to address the other parts of your PCI-DSS specific concerns.
My telco will only offer FCIP routing for long-distance disk replication, but my CIO wants to use Fibre Channel routing over CWDM, what do I do?
IBM XIV, DS8000 and DS5000 all support FC-based long distance replication across CWDM. However, if you don't have dark fiber, and your telco won't provide this option, you may need to re-negotiate your options.
My DS4800 sometimes reboots repeatedly, what should I do.
This was a known problem with microcode level 760.28, it was detecting a failed drive. You need to replace the drive, and upgrade to the latest microcode.
Should I use VMware snapshots or DS5000 FlashCopy?
VMware snapshots are not free, you need to upgrade to the appropriate level of VMware to get this function, and it would be limited to your VMware data only. The advantage of DS5000 FlashCopy is that it applies to all of your operating systems and hypervisors in use, and eliminates the consumption of VMware overhead. It provides crash-consistent copies of your data. If your DS5000 disk system is dedicated to VMware, then you may want to compare costs versus trade-offs.
Any truth to the rumor that Fibre Channel protocol will be replaced by SAS?
SAS has some definite cost advantages, but is limited to 8 meters in length. Therefore, you will see more and more usage of SAS within storage devices, but outside the box, there will continue to be Fibre Channel, including FCP, FICON and FCoE. The Fibre Channel Industry Alliance [FCIA] has a healthy roadmap for 16 Gbps support and 20 Gbps interswitch link (ISL) connections.
What about Fibre Channel drives, are these going away?
We need to differentiate the connector from the drive itself. Manufacturers are able to produce 10K and 15K RPM drives with SAS instead of FC connectors. While many have suggested that a "Flash-and-Stash" approach of SSD+SATA would eliminate the need for high-speed drives, IBM predicts that there just won't be enough SSD produced to meet the performance needs of our clients over the next five years, so 15K RPM drives, more likely with SAS instead of FC connectors, will continue to be deployed for the next five years.
We'd like more advanced hands-on labs, and to have the certification exams be more product-specific rather than exams for midrange disk or enterprise disk that are too wide-ranging.
Ok, we will take that feedback to the conference organizers.
IBM Tivoli Storage Manager is focused on disaster recovery from tape, how do I incorporate remote disk replication.
This is IBM's Unified Recovery Management, based on the seven tiers of disaster recovery established in 1983 at GUIDE conference. You can combine local recovery with FastBack, data center server recovery with TSM and FlashCopy manager, and combine that with IBM Tivoli Storage Productivity Center for Replication (TPC-R), GDOC and GDPS to manage disk replication across business continuity/disaster recovery (BC/DR) locations.
IBM Tivoli Storage Productivity Center for Replication only manages the LUNs, what about server failover and mapping the new servers to the replicated LUNs?
There are seven tiers of disaster recovery. The sixth tier is to manage the storage replication only, as TPC-R does. The seventh tier adds full server and network failover. For that you need something like IBM GDPS or GDOC that adds this capability.
All of my other vendor kit has bold advertising, prominent lettering, neon lights, bright colors, but our IBM kit is just black, often not even identifying the specific make or model, just "IBM" or "IBM System Storage".
IBM has opted for simplified packaging and our sleek, signature "raven black" color, and pass these savings on to you.
Bring back the SHARK fins!
We will bring that feedback to our development team. ("Shark" was the codename for IBM's ESS 800 disk model. Fiberglass "fins" were made as promotional items and placed on top of ESS 800 disk systems to help "identify them" on the data center floor. Unfortunately, professional golfer [<a href="http://www.shark.com/">Greg Norman</a>] complained, so IBM discontinued the use of the codename back in 2005.)
Where is Infiniband?
Like SAS, Infiniband had limited distance, about 10 to 15 meters, which proved unusable for server-to-storage network connections across data center floorspace. However, there are now 150 meter optical cables available, and you will find Infiniband used in server-to-server communications and inside storage systems. IBM SONAS uses Infiniband today internally. IBM DCS9900 offers Infiniband host-attachment for HPC customers.
We need midrange storage for our mainframe please?
In addition to the IBM System Storage DS8000 series, the IBM SAN Volume Controller and IBM XIV are able to connect to Linux on System z mainframes.
We need "Do's and Don'ts" on which software to run with which hardware.
IBM [Redbooks] are a good source for that, and we prioritize our efforts based on all those cards and letters you send the IBM Redbooks team.
The new TPC v4 reporting tool requires a bit of a learning curve.
The new reporting tool, based on Eclipse's Business Intelligence Reporting Tool [BIRT], is now standardized across the most of the Tivoli portfolio. Check out the [Tivoli Common Reporting] community page for assistance.
An unfortunate side-effect of using server virtualization like VMware is that it worsens management and backup issues. We now have many guests on each blade server.
IBM is the leading reseller of VMware, and understands that VMware adds an added layer of complexity. Thankfully, IBM Tivoli Storage Manager backups uses a lightweight agent. IBM [System Director VMcontrol] can help you manage a variety of hypervisor environments.
This was a great interactive session. I am glad everyone stayed late Thursday evening to participate in this discussion.
Continuing coverage of my week in Washington DC for the annual [2010 System Storage Technical University], I attended several XIV sessions throughout the week. There were many XIV sessions. I could not attend all of them. Jack Arnold, one of my colleagues at the IBM Tucson Executive Briefing Center, often presents XIV to clients and Business Partners. He covered all the basics of XIV architecture, configuration, and features like snapshots and migration. Carlos Lizarralde presented "Solving VMware Challenges with XIV". Ola Mayer presented "XIV Active Data Migration and Disaster Recovery".
Here is my quick recap of two in particular that I attended:
XIV Client Success Stories - Randy Arseneau
Randy reported that IBM had its best quarter ever for the XIV, reflecting an unexpected surge shortly after my blog post debunking the DDF myth last April. He presented successful case studies of client deployments. Many followed a familiar pattern. First, the client would only purchase one or two XIV units. Second, the client would beat the crap out of them, putting all kinds of stress from different workloads. Third, the client would discover that the XIV is really as amazing as IBM and IBM Business Partners have told them. Finally, in the fourth phase, the client would deploy the XIV for mission-critical production applications.
A large US bank holding company managed to get 5.3 GB/sec from a pair of XIV boxes for their analytics environment. They now have 14 XIV boxes deployed in mission-critical applications.
A large equipment manufacturer compared the offerings among seven different storage vendors, and IBM XIV came out the winner. They now have 11 XIV boxes in production and another four boxes for development/test. They have moved their entire VMware infrastructure to IBM XIV, running over 12,000 guest instances.
A financial services company bought their first XIV in early 2009 and now has 34 XIV units in production attached to a variety of Windows, Solaris, AIX, Linux servers and VMware hosts. Their entire Microsoft Exchange was moved from HP and EMC disk to IBM XIV, and experienced noticeable performance improvement.
When a University health system replaced two competitive disk systems with XIV, their data center temperature dropped from 74 to 68 degrees Fahrenheit. In general, XIV systems are 20 to 30 percent more energy efficient per usable TB than traditional disk systems.
A service provider that had used EMC disk systems for over 10 years evaluated the IBM XIV versus upgrading to EMC V-Max. The three year total cost of ownership (TCO) of EMC's V-Max was $7 Million US dollars higher, so EMC counter-proposed CLARiiON CX4 instead. But, in the end, IBM XIV proved to be the better fit, and now the customer is happy having made the switch.
The manager of an information communications technology service provider was impressed that the XIV was up and running in just a couple of days. They now have over two dozen XIV systems.
Another XIV client had lost all of their Computer Room Air Conditioning (CRAC) units for several hours. The data center heated up to 126 degrees Fahrenheit, but the customer did not lose any data on either of their two XIV boxes, which continued to run in these extreme conditions.
Optimizing XIV Performance - Brian Cormody
This session was an update from the [one presented last year] by Izhar Sharon. Brian presented various best practices for optimizing the performance when using specific application workloads with IBM XIV disk systems.
Oracle ASM: Many people allocate lots of small LUNs, because this made sense a long time ago when all you had was just a bunch of disks (JBOD). In fact, many of the practices that DBAs use to configure databases across disks become unnecessary with XIV. Wth XIV, you are better off allocating a few number of very large LUNs from the XIV. The best option was a 1-volume ASM pool with 8MB AU stripe. A single LUN can contain multiple Oracle databases. A single LUN can be used to store all of the logs.
VMware: Over 70 percent of XIV customers use it with VMware. For VMFS, IBM recommends allocating a few number of large LUNs. You can specify the maximum of 2181 GB. Do not use VMware's internal LUN extension capability, as IBM XIV already has thin provisioning and works better to allow XIV to do this for you. XIV Snapshots provide crash-consistent copies without all the VMware overhead of VMware Snapshots.
SAP: For planning purposes, the "SAPS" unit equates roughly to 0.4 IOPS for ERP OLTP workloads, and 0.6 IOPS for BW/BI OLAP workloads. In general, an XIV can deliver 25-30,000 IOPS at 10-15 msec response time, and 60,000 IOPS at 30 msec response time. With SAP, our clients have managed to get 60,000 IOPS at less than 15 msec.
Microsoft Exchange: Even my friends in Redmond could not believe how awesome XIV was during ESRP testing. Five Exchange 2010 servers connected two a pair of XIV boxes using the new 2TB drawers managed 40,000 mailboxes at the high profile (0.15 IOPS per mailbox). Another client found four XIV boxes (720 drives) was able to handle 60,000 mailboxes (5GB max), which would have taken over 4000 drives if internal disk drives were used instead. Who said SANs are obsolete for MS Exchange?
Asynchronous Replication: IBM now has an "Async Calculator" to model and help design an XIV async replication solution. In general, dark fiber works best, and MPLS clouds had the worst results. The latest 10.2.2 microcode for the IBM XIV can now handle 10 Mbps at less than 250 msec roundtrip. During the initial sync between locations, IBM recommends setting the "schedule=never" to consume as much bandwidth as possible. If you don't trust the bandwidth measurements your telco provider is reporting, consider testing the bandwidth yourself with [iPerf] open source tool.
IBM Tivoli Storage Productivity Center version 4.1 Overview
In conferences like these, there are two types of product-level presentations. An "Overview" explains how products 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. This session was an Overview of [Tivoli Storage Productivity Center], plus some information of IBM's Storage Enterprise Resource Planner [SERP] from IBM's acquisition of NovusCG.
I was one of the original lead architects of Productivity Center many years ago, and was able to share many personal experiences 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.
I would like to thank my colleague Harley Puckett for his assistance in putting the finishing touches on this presentation. This was my best attended session of the week, indicating there is a lot of interest in this product in particular, and managing a heterogeneous mix of storage devices in general. To hear a quick video introduction, see Harley Puckett's presentation at the [IBM Virtual Briefing Center].
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 performing ILM assessments for clients, and now there are dozens of IBM practitioners in Global Services and Lab Services that do this full time. This is a topic I cover frequently at the IBM Executive Briefing Center [EBC], because it addresses several 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
When I presented ILM last year, I did not get many attendees. This time I had more, perhaps because of the recent announcement of ILM and HSM support in IBM SONAS and our April announcement of IBM DS8700 Easy Tier has renewed interest in this area.
I have safely returned back to Tucson, but have still a lot of notes of the other sessions I attended, so will cover them this week.
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.