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To: linux-kernel@vger.kernel.org
From: Lutz Vieweg <lvml@5t9.de>
Subject: Re: What happened to TRIM support for raid linear/0/1/10?
Date: Wed, 08 Aug 2012 19:58:56 +0200
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On 08/08/2012 03:10 PM, Holger Kiehl wrote:
> Personally, I would think that TRIM support MD would be a very good thing.

That's one thing I am waiting for, too.

We had to implement a somewhat clumsy user-space application which does
the trick for us - but that is an ugly work-around, as it has to allocate
most of the free space on a filesystem for at least a little while (to know
what blocks it can discard).

Without periodic discard runs, our SSD-equipped servers suffer a ~50% write
performance penalty, so this feature is not just a cosmetic issue to us.

Regards,

Lutz Vieweg