The "corporate bloggers" from the various storage vendors often mention their opinions about IBM products. Sometimes, they say something nice, and other times they poke fun. It's good to read the various opinions. Most are well-thought and well-written.

EMC blogger Chuck Hollis has a post about the various categories that industry analyst IDC used for external controller-based disk in their most recentQ4 Storage Scorecard.I agree with Chuck that it is good to have independent analysts that take an objective look across all storage vendors to provide the facts on various makes and models. Both IBM and EMC took marketshare in 4Q, so we cancongratulate ourselves and each other for the efforts needed to make this happen.

Chuck mentions that while EMC and HDS high-end boxes are similar, perhaps IBM's "DS" series is different enough to question putting it in the same "high-end" category. It's not clear if Chuck is poking fun at the fact that theIBM DS family spans multiple categories; or an admission thatthe IBM DS8300 Turbo is faster than the EMC DMX-3 and HDS USP offerings. Perhaps we need a new categorycalled "super high-end"?

IDC doesn't publish their data by price band, but we can infer from the products in each how they decidedwhich products were grouped into which categories. Let's examine the entire IBM DS family in the various categories.

Entry Level

Our newest offering is the IBM System Storage DS3000 series. Some analysts call this category "low end", but IBM prefers using "entry level". These have an attractivelow acquisition price, very easy to set up, and are intended for the Intel and AMD servers, such as IBMBladeCenter, System x, as well as servers from HP and Dell. Disk arrays in this category typically have listprices below $50,000 USD.

Midrange

Our midrange offering is the IBM System Storage DS4000 series. These are designed for Linux, UNIX and Windows based workloads.Some call these server platforms "open systems", or sometimes "distributed systems". The DS4000 systems are rack-optimized modularunits, providing plenty of options and trade-offs between price and performance for price-sensitive customers.The "high end" model of the DS4000 series is the DS4800, and has very impressive performance characteristics.Disk arrays in this category typically have list prices in the $50,000 to $299,000 USD range.

Enterprise Class

IBM System Storage DS6000 seriesis one of our enterprise class offerings. DS6000 offers mainframe attachment comparable to what EMC DMX or HDS USP offer for their "enterprise class" or "high end" models, but uses substantially less power and in a much more compact modular rack-optimized packaging. Disk arrays in this category typically have list prices at $300,000 USD and above.

Super High End

Perhaps IBM and EMC can work together to petition IDC to adopt this as a new category, based on performance,rather than list price. Is the storage marketplace ready for a fourth category?As Chuck mentioned on his blog, IBM is #1 for mainframe disk storage, and perhaps it is because the IBM System Storage DS8000 Turbo series does so well on most mainframe workloads. No offering from EMC or HDS meet or beat the SPC benchmarks for the DS8000 Turbo. You can see the results in the Executive Summary or read the Full Report.

Thanks to IBM's innovative Adaptive ReplacementCache algorithm, IBM DS8000 performance shines best handling read-intensive random-access workloads that mainframes do most often. These types of workload are modeled by the SPC-1 benchmark. In cases of write-intensive, sequential processing, the differences are less substantial, as disk arrays from all manufacturers drop down to the native performance capabilities of the 10K and 15K RPM drives.

I'll give you a real example. Not long ago, I waspart of a team to help resolve a performance bottleneck on-site at the customer location. The customer had an interesting "composite application" where data was processed on AIX platform (IBM System p), which passed the data to a Linux partition running on the IBM System z mainframe,which in turn used Java SQL to post updates to a DB2 database on z/OS partition, which then wrote out through FICON adapters to an HDS USP device. IBM and HDS worked together to help the customer figure out why they weregetting disappointing throughput and response times. IBM brought in experts on AIX, TCP/IP, Java, Linux, z/OS and FICON. HDS had their experts too, and tried to improve performance by quadrupling the storage capacity, and spreading the data out across more spindles. That didn't work. As it turns out, HDS disk just couldn't deliver the performance required. The software and mainframe were all well tuned. They replaced the HDS withan IBM DS8000 array, and it met all the service level requirements. Problem solved.

The problem with having this new "super high end" category, of course, is that only IBM plays in it, so it wouldn'toffer the marketplace much of a comparison. For now, we'll just have to settle for being the fastest in the samecategory as EMC DMX and HDS USP.

Storage is a competitive marketplace.Both EMC and HDS are reputable companies that make quality products that attach to IBM System z mainframe servers. Not all workloads are mission-critical or performance-sensitive. For less critical workloads, perhaps you may find EMC or HDS performance is "good enough".

But if performance is important to you, you should consider IBM on your list of vendors for your next purchase decision. Let IBM help you prove it to yourself, running your specific workloads side by side with your existing equipment.

technorati tags: IBM, EMC, Chuck Hollis, IDC, Q4, storage, disk,scorecard, z/OS, AIX, Linux, Java, DB2, HDS, USP, DMX, SPC, benchmarks, mainframe, System Storage, DS3000, DS4000, DS6000, DS8000, DS8300, Turbo

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