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From: Kirk Strauser <kirk@strauser.com>
To: Kris Kennaway <kris@freebsd.org>
Date: Thu, 5 Jun 2008 16:17:53 -0500
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Message-Id: <200806051617.54400.kirk@strauser.com>
Cc: freebsd-questions@freebsd.org
Subject: Re: Poor read() performance, and I can't profile it
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On Thursday 05 June 2008, Kris Kennaway wrote:
> Kirk Strauser wrote:
> ktrace(1) and check for the buffer size in use. It is probably too
> small.
>
> Kris
It seems to be doing a lot of read()s with 4096-byte buffers. Is that what
you mean? It's also doing a lot of lseek()s to what is likely the current
position anyway (example: seek to 0x00, read 16 bytes, seek to 0x10, etc.).
Would that make a difference, or should that be a NOP?
--
Kirk Strauser