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Message-ID: <7d15175e0612212139p4fc2fd27x7acb3473701b2c35@mail.gmail.com>
Date: Fri, 22 Dec 2006 11:09:14 +0530
From: "Bhanu Kalyan Chetlapalli" <chbhanukalyan@gmail.com>
To: "Manish Regmi" <regmi.manish@gmail.com>
Subject: Re: Linux disk performance.
Cc: kernelnewbies@nl.linux.org, linux-kernel@vger.kernel.org
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On 12/22/06, Manish Regmi <regmi.manish@gmail.com> wrote:
> On 12/22/06, Bhanu Kalyan Chetlapalli <chbhanukalyan@gmail.com> wrote:
> >
> > I am assuming that your program is not seeking inbetween writes.
> >
> > Try disabling the Disk Cache, now-a-days some disks can have as much
> > as 8MB write cache. so the disk might be buffering as much as it can,
> > and trying to write only when it can no longer buffer. Since you have
> > an app which continously write copious amounts of data, in order,
> > disabling write cache might make some sense.
> >
>
> Thanks  for the suggestion but the performance was terrible when write
> cache was disabled.

Performance degradation is expected. But the point is - did the
anomaly, that you have pointed out, go away? Because if it did, then
it is the disk cache which is causing the issue, and you will have to
live with it. Else you will have to look elsewhere.

> --
> ---------------------------------------------------------------
> regards
> Manish Regmi
>
> ---------------------------------------------------------------
> UNIX without a C Compiler is like eating Spaghetti with your mouth
> sewn shut. It just doesn't make sense.
>


-- 
There is only one success - to be able to spend your life in your own way.
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