Date: Sun, 19 Mar 2006 11:47:51 +0800
From: Wu Fengguang <wfg@mail.ustc.edu.cn>
To: Jon Smirl <jonsmirl@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 00/23] Adaptive read-ahead V11
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On Sat, Mar 18, 2006 at 10:10:43PM -0500, Jon Smirl wrote:
> This is probably a readahead problem. The lighttpd people that are
> encountering this problem are not regular lkml readers.
> 
> http://bugzilla.kernel.org/show_bug.cgi?id=5949

[QUOTE]
        My general conclusion is that since they were able to write a user
        space implementation that avoids the problem something must be broken
        in the kernel readahead logic for sendfile().

Maybe the user space solution does the trick by using a larger window size?

IMHO, the stock read-ahead is not designed with extremely high concurrency in
mind. However, 100 streams should not be a problem at all.

Wu
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