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Date: Wed, 31 Aug 2011 02:29:33 +0400
From: Lev Serebryakov <lev@FreeBSD.org>
Organization: FreeBSD
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To: Kirk McKusick <mckusick@mckusick.com>, freebsd-fs@freebsd.org
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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., 2:14:04:

>   I'll try this experiment with mmap() and touching every 4096-th byte of
> mapped memory instead of read(2).
  Strange enough, it gives only 40-50MiB/s and results are very
 consistent.

  It really surprise me. I didn't think, that there will be so much
difference, I was sure, that it will be almost equivalent speed.

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