I just read Brian Beach’s blog for Backblaze and am amazed: His comparison of Backblaze storage pods that use consumer drives with enterprise storage controllers that contain enterprise disk drives from EMC and Dell is like comparing apples and flying pigs.
EMC and Dell both have detailed information on which metrics are evaluated before they decide that a drive is going to fail. This is often referred to as sparing a drive by looking at the SMART data and it prompts admins to begin the rebuild process before the drive dies. There is nothing in the blog that discusses this. In addition Mr. Beach does not explain what SMART data he collects and how it is used. Is it the same that EMC and Dell have collected and researched for years, or just the basic information that is published – not the special, priveledged information that the drive vendors share with their partners?
Another issue I see is that RAID controllers will spare a drive if the performance is not up to specification over a certain period of time. For example I know of one RAID vendor that kills a drive if it does not respond in five seconds, far less than most drive timeout values. Also, are we comparing enterprise drives that are 3 years old with brand new consumer drives? What are the brands, what are the ages of the comparisons?
There was a study a few years ago that compared FC drives to SATA drives. The FC drives in question were from the early 2000s and have a known bearing issue and the SATA drives were from the mid-2000s (about 3 years later) and had no known issues. Guess what was better? Without a great deal more detailed information, I consider this study lacking technical rigor and it provides potentially very misleading information. I suspect that after today the major drive vendors will be quietly saying something. At least I hope so, as without more detailed information this study provides no new information.
Labels: disk drives, enterprise storage, Backblaze
posted by: Henry Newman
The storage news these days could seemingly be published by The Onion. We have EMC and Pure Storage with dueling lawsuits, we have OCZ filing for bankruptcy, we have Violin Memory shares dropping like a rock on bad sales news – and this is just information over the last week or so. This seems like a great deal of turmoil even for our volatile industry. I am not totally surprised about each one of these, but all of them happening in such a short period of time seems like an odd coincidence.
We all know that there is lots of turmoil in the solid state drive business. The failure of OCZ is not and should not be a surprise to anyone following them, and if the rumors were true I am sure that someone at OCZ should be kicking themselves for not selling to Seagate. But this is happening about the same time that Violin Memory announced a huge loss with no end in sight. This seemed like an odd time for both of these things to come out.
The strangest one of all is the spat between EMC and Pure Storage. Sales people often change companies, and of course Pure Storage would want to get some ex-EMCers to understand customers and markets. What strikes me as very odd – even more than odd, but strange – is that the sales people are not clearly thinking things out. It is clear that the flash market is having some significant issues and that EMC has just announced products that will compete head to head with a number of flash vendors. Why jump to Pure Storage just as this is happening and right in the middle major market changes to flash? Maybe The Onion should have a section on storage. The news might make more sense there.
Photo courtesy of Shutterstock.
Labels: SSD, enterprise storage, Flash Storage
posted by: Henry Newman