How can I optimize the speed and lifetime of SSDs used in a RAID-0?

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I have two SSDs in RAID-0 on a Windows 7, 64-bit system. Since it appears that TRIM still isn't supported with any RAID configuration of SSDs, what are some tips/workarounds that I can use?

Some things, but not limited to, that I would like to optimize are:

  • file write sizes to each disk to best match each 'block' sizes that are erased by the SSD.
  • speed of the RAID reads/writes
  • overall health of the drives
  • Settings of the RAID (i.e. stripe size)
  • any other 'tips' that might be considered for a RAID of SSD's

James Mertz

Posted 2011-05-07T22:38:03.510

Reputation: 24 787

No idea, why not post them over to me and I am sure I can work some things out :) – William Hilsum – 2011-05-07T23:00:10.137

I'm curious about why you need two SSDs in RAID 0 in the first place. To aggregate the space for convenience? Improved sequential access? I know this really doesn't help answer your question, but my tip would be not to do this. – sblair – 2011-05-08T00:34:28.777

@Sblair this was done originally as a test to see if there was a significant increase in speed for a blog post. As there was, the thought was/is that one could purchase two smaller, less-expensive SSD's, then RAID them and get a faster experience cheaper. Yes, you can expect this to be blogged in the future. ;)

– James Mertz – 2011-05-08T00:54:12.813

Answers

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I would suggest not using RAID0 for good SSDs. A good modern SSD is unlikely to be your bottleneck for most real-world access patterns, at least not in a way RAID-0 is going to help a lot.

Unless of course you are linking a pair of drives together this way in order to have one large volume rather than two separate ones, rather than due to speed concerns...

Some SSD controllers will take writing a block of all 0s to mean that the block is free to be TRIMed (and instead of storing the location of the block in the appropriate index store a sentinel value that means "if you are asked for this block, just return a load of 0s"). If your drives do this then occasionally writing over your free space with 0s would help, using sdelete or similar in zero-only mode. Not terribly efficient of course, and make sure your drives will react this way otherwise you will be making the situation worse rather than better.

David Spillett

Posted 2011-05-07T22:38:03.510

Reputation: 22 424

The goal is to be able to have two cheaper, smaller spaced drives that give me more space but not as expensive – James Mertz – 2011-05-09T20:16:47.493

In that case you'll need to look into if those drives auto-trim for all-zero blocks as described above. Also make sure you have a good backup regime as you are increasing your chance of drive failure noticeably over that of a single drive configuration. – David Spillett – 2011-05-09T22:54:48.640

For info, this post describes how to "zero" an entire SSD, under Windows.

– sblair – 2011-05-15T00:52:24.727

Raid 0 on SSD drives is a bad idea IMO. 2x the chance of data loss. – Jeff F. – 2011-05-26T17:51:46.100

Asked: 2011-05-07T22:38:03.510

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