

IBM XIV Gen3 SSD Caching versus EMC VFCacheHave you ever noticed that sometimes two movies come out that seem eerily similar to each other, released by different studios within months or weeks of each other? My sister used to review film scripts for a living, she would read ten of them and have to pick her top three favorites, and tells me that scripts for nearly identical concepts came all the time. Here are a few of my favorite examples:
(I think I made my point with just a few examples. A more complete list can be found on [Sam Greenspan's 11 Points website].) This is different than copy-cat movies that are re-made or re-imagined many years later based on the previous successes of an original. Ever since my blog post [VPLEX: EMC's Latest Wheel is Round] in 2010 comparing EMC's copy-cat product that came our seven years after IBM's SAN Volume Controller (SVC), I've noticed EMC doesn't talk about VPLEX that much anymore. This week, IBM announced [XIV Gen3 Solid-State Drive support] and our friends over at EMC announced [VFCache SSD-based PCIe cards]. Neither of these should be a surprise to anyone who follows the IT industry, as IBM had announced its XIV Gen3 as "SSD-Ready" last year specifically for this purpose, and EMC has been touting its "Project Lightning" since last May. Fellow blogger Chris Mellor from The Register has a series of articles to cover this, including [EMC crashes the server flash party], [NetApp slaps down Lightning with multi-card Flash flush], [HP may be going the server flash route], and [Now HDS joins the server flash party]. Fellow blogger Chuck Hollis from EMC has a blog post [VFCache means Very Fast Cache indeed] that provides additional detail. Chuck claims the VFCache is faster than popular [Fusion-IO PCIe cards] available for IBM servers. I haven't seen the performance spec sheets, but typically SSD is four to five times slower than the DRAM cache used in the XIV Gen3. The VFCache's SSD is probably similar in performance to the SSD supported in the IBM XIV Gen3, DS8000, DS5000, SVC, N series, and Storwize V7000 disk systems. Nonetheless, I've been asked my opinions on the comparison between these two announcements, as they both deal with improving application performance through the use of Solid-State Drives as an added layer of read cache. (FTC Disclosure: I am both a full-time employee and stockholder of the IBM Corporation. The U.S. Federal Trade Commission may consider this blog post as a paid celebrity endorsement of IBM servers and storage systems. This blog post is based on my interpretation and opinions of publicly-available information, as I have no hands-on access to any of these third-party PCIe cards. I have no financial interest in EMC, Fusion-IO, Texas Memory Systems, or any other third party vendor of PCIe cards designed to fit inside IBM servers, and I have not been paid by anyone to mention their name, brands or products on this blog post.) The solutions are different in that IBM XIV Gen3 the SSD is "storage-side" in the external storage device, and EMC VFCache is "server-side" as a PCI Express [PCIe] card. Aside from that, both implement SSD as an additional read cache layer in front of spinning disk to boost performance. Neither is an industry first, as IBM has offered server-side SSD since 2007, and IBM and EMC have offered storage-side SSD in many of their other external storage devices. The use of SSD as read cache has already been available in IBM N series using [Performance Accelerator Module (PAM)] cards. IBM has offered cooperative caching synergy between its servers and its storage arrays for some time now. The predecessor to today's POWER7-based were the iSeries i5 servers that used PCI-X IOP cards with cache to connect i5/OS applications to IBM's external disk and tape systems. To compete in this space, EMC created their own PCI-X cards to attach their own disk systems. In 2006, IBM did the right thing for our clients and fostered competition by entering in a [Landmark agreement] with EMC to [license the i5 interfaces]. Today, VIOS on IBM POWER systems allows a much broader choice of disk options for IBM i clients, including the IBM SVC, Storwize V7000 and XIV storage systems. EMC is not the first to manufacture an SSD-based PCIe card. Last summer, my friends at Texas Memory Systems [TMS] gave away a [RAMsan-70 PCIe card] at an after-party on [Day 2 of the IBM System Storage University]. Can a little SSD really help performance? Yes! An IBM client running a [DB2 Universal Database] cluster across eight System x servers was able to replace an 800-drive EMC Symmetrix by putting eight SSD Fusion-IO cards in each server, for a total of 64 Solid-State drives, saving money and improving performance. DB2 has the Data Partitioning Feature that has multi-system DB2 configurations using a Grid-like architecture similar to how XIV is designed. Most IBM System x and BladeCenter servers support internal SSD storage options, and many offer PCIe slots for third-party SSD cards. Sadly, you can't do this with a VFCache card, since you can have only one VFCache card in each server, the data is unprotected, and only for ephemeral data like transaction logs or other temporary data. With multiple Fusion-IO cards in an IBM server, you can configure a RAID rank across the SSD, and use it for persistent storage like DB2 databases. Here then is my side-by-side comparison:
IBM has the advantage that it designs and manufactures both servers and storage, and can design optimal solutions for our clients in that regard.
Tags:  aix vfcache ramsan +systems system+x svc emc project+lightning pcie ibm+i fusion-io gen3 vmware xiv ssd pci-x texas+memory+systems power solid+state+drives ibm cache vmotion dram live+partition+mobility |
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#ibmtechu Day 2 IBM Storage University - Solutions Expo![]() I gotten several emails expressing worry that I have fallen off the face of th earth. The last two weeks have been educational and eye-opening for me. I can't provide details in my blog, so I will just say that it involved government agencies that IBM refers to as "dark accounts", and that I am now back safely in the USA. Between adjusting to time zone differences, ridiculously long hours, and restricted access to the internet, I was unable to blog lately. ![]() ![]() Instead, I will resume my coverage of the [IBM System Storage Technical University 2011]. The "Solutions Expo" runs Monday evening through Wednesday lunch. This is a chance for people to explore all the solutions that are part of IBM's large "eco-system" for IBM System storage and System x products. There were several sponsors for this event. ![]() As is often the case at these conferences, the various booths hand out fun items. The hot items this year were tie-dyed tee-shirts from Qlogic, and propeller beanies from the IBM rack and power systems team. Here is Amanda, one of the bartenders showing off the latter. ![]() After the expo on Tuesday night, my friends at [Texas Memory Systems] held an after-party. Unlike the pens, tee-shirts and keychains at the Expo, these guys had a raffle for real storage products. Here is Erik Eyberg handing out a RamSan PCIe card, valued at $14,000 or so. IBM recently certified the TMS RamSan as External SSD storage for the IBM SAN Volume Controller (SVC). The SVC can optimize performance using this for automated sub-LUN tiering with the IBM System Storage Easy Tier feature.
Tags:  easy+tier tms qlogic ibm storage university ramsan svc |