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From: Nick Piggin <nickpiggin@yahoo.com.au>
To: Michael Stiller <ms@2scale.net>
Subject: Re: howto boost write(2) performance?
Date: Tue, 9 Oct 2007 20:25:34 +1000
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On Tuesday 09 October 2007 23:50, Michael Stiller wrote:
> Hi list,
>
> i'm developing an application (in C) which needs to write about
> 1Gbit/s (125Mb/s) to a disk array attached via U320 SCSI.
> It runs on Dual Core 2 Xeons @2Ghz utilizing kernel 2.6.22.7.
>
> I buffer the data in (currently 4) 400Mb buffers and use write(2) in a
> dedicated thread to write them to the raw disk (no fs).
>
> The write(2) performance is not good enough, the writer threads take to
> much time, and i ask you for ideas, howto to boost the write
> performance.

The kernel really cannot sustain 125MB/s? I assume the disk
array is capable?

Where is the bottleneck? Does it keep all disks busy, or are
the CPUs overloaded?
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