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Subject: Re: Samsung 840 Pro SSD and quirks
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From: Borja Marcos <borjam@sarenet.es>
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To: Steven Hartland <killing@multiplay.co.uk>
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On Sep 1, 2014, at 5:44 PM, Steven Hartland wrote:

> We saw a noticable performance increase on 4k on our 8TB 840
> array but I too couldn't find any concrete information either.
>=20
> If anyone has this info and can confirm either way that would
> be great.

I stand corrected. I have done some benchmarks with just two Samsung =
SSDs (zpool with two disks, no mirroring) and indeed I get better =
performance with 4 KB blocks.

I did my original tests with 12 disks and some other bottleneck was =
hiding the performance difference.

In both cases, anyway, Trim was working unless the system lies.





Thanks!