Re: Software RAID and TRIM

On Mon, 18 Jul 2011, David Brown wrote:

First, I'd like to say that I've done more testing, and found that even after very prolonged, sustained heavy use, the (Intel 510) SSDs I partitioned 50/50 with half left unused didn't show any degradation in performance. That's after about a week of constant writing/erasing.

If your disks are reasonably full, then TRIM will not help much because the garbage collection will be desperately trying to piece together small bits into complete erase blocks, and your performance will drop through the floor.

However, it won't drop as low as it would without TRIM in the same situation. But with a continuous heavy workload, even TRIM won't help, and over-provisioning is the way to go.

Best,

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Tom De Mulder [off-list ref] - Cambridge University Computing Service
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