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MS Researchers Call Moving Server Storage To SSDs a Bad Idea
An anonymous reader writes "As an IT administrator did you ever think of replacing disks by SSDs? Or using SSDs as an intermediate caching layer? A recent paper by Microsoft researchers provides detailed cost/benefit analysis for several real workloads. The conclusion is that, for a range of typical enterprise workloads, using SSDs makes no sense in the short to medium future. Their price needs to decrease by 3-3000 times for them to make sense. Note that this paper has nothing to do with laptop workloads, for which SSDs probably make more sense (due to SSDs' ruggedness)."
News at 11!
This is an ACM article behind a paywall.
How about a slashdot policy of not linking to articles behind paywalls?
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Hm. I was thinking the same thing about the ACM subscription.
I'm a 2000 man.
SSD is already cheaper per gig than some SAS drives. Also, 3-3000 times? What the hell sort of estimate is that?
It's called "pulling numbers out of your ass".
FAT chance.........
What do you mean, an african or european ass?
Page 1 Microsoft Research Ltd. Technical Report MSR-TR-2008-169, November 2008 Not a thing to do with it.
No statement is true, not even this one.
These days, hard drives are cheaper than tapes and will hold their data longer and more compatibly.
That's entirely false.
Hard drives are vastly cheaper than tape drives, but enterprise quality tape is stil cheaper than enterprise quality HDDs.
Enterprise tape has a proven 20-year shelf life, no HDD does.
I wrote new commercial software that could (and did) work with IBM's 9-track tape format in 1994, 30 years after it released, and there is still hardware and software in use today that can read that hardware format - 45 years of compatibility. The abstract format - ANSI tape labels - is still in niche use for newly saved data today. DLT format is 25 years old, and while I'm not sure you can buy a new drive that reads the original DLT format, used drives are still easy to come by and you can connect them to new SCSI cards.
How easy is it to read an MFM drive (assuming there are more than 0 in the world that still work)? That format is 30 years old, and it would be a real challenge to find a slot on a modern PC that would take an MFM controller, vastly harder than reading a DLT tape. FAT is also about 30 years old, but disk formats older than that are basically extinct.
Socialism: a lie told by totalitarians and believed by fools.
Microsoft researchers provides detailed cost/benefit analysis for several real workloads.
If Microsoft researchers report that SSD's are not cost effective storage, it means that Microsoft is not getting any revenue from SSD storage. Or that they're behind on incorporating SSD's into the server stack. Or they caught blind-sided by the trend like they did with netbooks and are now scrambling to explain why they didn't see it coming. Oh, we found that wasn't cost effective, so we didn't incorporate it.
I really miss the days Microsoft had it together. There was a time they were great to work with. Now they seem like the Three Stooges Do IT. SSD, eh? Oh, a wise guy! SMACK! Wo-wo-wo-wo!
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Windows 2020 will have the same features as Open Solaris 10, just wait and see. They will be able to use a SSD as a cache reader I swear!
They could call it... ReadyBoost.
http://blogs.sun.com/brendan/entry/test has some background information, and http://blogs.sun.com/brendan/entry/l2arc_screenshots and http://blogs.sun.com/brendan/entry/my_sun_storage_7410_perf has some performance numbers.
Basically, what Sun is claiming is that by adding a SSD cache layer you can improve IOPS by about 5x, for what amounts to a really small amount of money for say a 100tb system. This is being marketed quite heavily by Sun as well. (The numbers look convincing, and the prices for the Sun Storage servers are certainly very competitive, well, compared to say NetApp.)
IMHO this is just a repeat of the well known Microsoft tactic of spreading massive amounts of FUD about any competing technology that you can't reproduce yourself - you'll have to wait until Windows Server 2013 for this.
Since this paper is focused on solid-state storage, and wear is a novel, SSD-specific phenomenon, we include it in our device models. Currently we do not model other failures, such as mechanical failures in disks.
The correct approach to incomplete data is, of course, to gather complete data, and they have no excuse here, because there is PLENTY of data on mechanical drive failure rates. However, if you are not willing to do that, the least you can do is ignore the data equally on both sides. The authors' failure to treat both sides equally leads to a hopelessly biased and skewed analysis.
I just finished the reading the paper.
The paper boils down to this:
SSD disk when measured against IOPS, Watts, and Capacity in relation to cost based on several different server types is not cost effective yet. Depending on the type of server costs need to come down at least 3 fold, and under some scenarios as much as 3000 times. Hosting MP3s that are largely sequental, low write storage SSDs are 3000 times over priced. For insaine random IO scenarios that need to come down 3 fold to make it worth it compared to conventional drives.
Depending on the type of server they can perform worse then standard mechanical disks.
They found no advantage to 15k RPM drives versus 10k RPM drives when cost is factored in.
SSD drives pay for themselves in power saving in about 5 years, well past their expected longevity.
Mechanical disks wear out more or less independant of their data load, SSDs wear out proportional to their data load.
SSDs do not handle tiny files very well due to how data is written.
I see nothing in the paper that is pro-microsoft, rather straight dealing on the drives themselves.
I would suggest MOD-TROLL any evanglest on any side of the OS wars as this paper doesn't seem to deal with OS touting.
It was a boring but informative read.
-=[ Who Is John Galt? ]=-
ext-remely unlikely.
They could grip it by the husk!
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
Stop with the puns or you'll end up in prison with Reiser.