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Date: Wed, 31 Aug 2011 02:31:55 +0400
From: Lev Serebryakov <lev@FreeBSD.org>
Organization: FreeBSD Project
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To: Kirk McKusick <mckusick@mckusick.com>
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Cc: freebsd-fs@freebsd.org
Subject: Re: Very inconsistent (read) speed on UFS2
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Hello, Kirk.
You wrote 31 =E0=E2=E3=F3=F1=F2=E0 2011 =E3., 0:09:12:

> memory faster than the cleanup thread can produce it. The result is
> that your read idles (e.g., appears to run slowly). It is random because
> it depends on when you run out of memory.
   BTW, it could explain why some runs are slower than other. But my
 situation looks like opposite: some runs much faster than others. And
 it could not be read-from-cache if VM is sane. It is hard to belive,
 that VM will store 0.5GiB of read-once data when another 5GiB was
 read after that only in 2GiB of physical memory

--=20
// Black Lion AKA Lev Serebryakov <lev@FreeBSD.org>