A Look at Enterprise Performance of Intel SSDs

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• ssj4Gogeta - Thursday, February 9, 2012 - link

  I think what you're forgetting here is that the 90% or 100% figures are _including_ the extra work that an SSD has to do for writing on already used blocks. That doesn't mean the data is incompressible; it means it's quite compressible.
  For example, if the SF drive compresses the data to 0.3x its original size, then including all the extra work that has to be done, the final value comes out to be 0.9x. The other drives would directly write the data and have an amplification of 3x.

• jwilliams4200 - Thursday, February 9, 2012 - link

  No, not at all. The other SSDs have a WA of about 1.1 when writing the same data.

• Anand Lal Shimpi - Thursday, February 9, 2012 - link

  Haha yes I do :) These SSDs were all deployed in actual systems, replacing other SSDs or hard drives. At the end of the study we looked at write amplification. The shortest use case was around 2 months I believe and the longest was 8 months of use.
  
  This wasn't simulated, these were actual primary use systems that we monitored over months.
  
  Take care,
  Anand

• Ryan Smith - Thursday, February 9, 2012 - link

  Indeed. I was the "winner" with the highest write amplification due to the fact that I had large compressed archives regularly residing on my Vertex 2, and even then as Anand notes the write amplification was below 1.0.

• jwilliams4200 - Thursday, February 9, 2012 - link

  And still you dodge my question.
  
  If the Sandforce controller can achieve decent compression, why did it not do better than the Intel 320 in the endurance test in this article?
  
  I think the answer is that your "8 month study" is invalid.

• Anand Lal Shimpi - Thursday, February 9, 2012 - link

  SandForce can achieve decent compression, but not across all workloads. Our study was limited to client workloads as these were all primary use desktops/notebooks. The benchmarks here were derived from enterprise workloads and some tasks on our own servers.
  
  It's all workload dependent, but to say that SandForce is incapable of low write amplification in any environment is incorrect.
  
  Take care,
  Anand

• jwilliams4200 - Friday, February 10, 2012 - link

  If we look at the three "workloads" discussed in this thread:
  
  (1) anandtech "enterprise workload"
  
  (2) xtremesystems.org client-workload obtained by using data actually found on user drives and writing it (mostly sequential) to a Sandforce 2281 SSD
  
  (3) anandtech "8 month" client study
  
  we find that two out of three show that Sandforce cannot achieve decent compression on realistic data.
  
  I think you should repeat your "client workload" tests and be more careful with tracking exactly what is being written. I suspect there was a flaw in your study. Either benchmarks were run that you were not aware of, or else it could be something like frequent hibernation where a lot of empty RAM is being dumped to SSD. I can believe Sandforce can achieve a decent compression ratio on unused RAM! :)

• RGrizzzz - Wednesday, February 8, 2012 - link

  What the heck is your site doing where you're writing that much data? Does that include the Anandtech forums, or just Anandtech.com?

• extide - Wednesday, February 8, 2012 - link

  Probably logs requests and browser info and whatnot.

• Stuka87 - Wednesday, February 8, 2012 - link

  That most likely includes the CMS and a large amount of the content, the Ad system, our users accounts for commenting here, all the Bench data, etc.
  
  The forums would use their own vBulletin database. But most likely run on the same servers.