Re: [resent PATCH] Re: very slow parallel read performance

From: Marc (pcg@goof.com)
Date: Sat Aug 25 2001 - 14:35:36 EST


On Sat, Aug 25, 2001 at 08:15:44PM +0100, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> How much disk and bandwidth can you afford. With vsftpd its certainly over
> 1000 parallal downloads on a decent PII box

exactly this is a point: my disk can do 5mb/s with almost random seeks,
and linux indeed reads 5mb/s from it. but the userpsace process doing
read() only ever sees 2mb/s because the kernel throes away all the nice
pages.

I doubt vsftpd would help at all.

(one can easily get 2000 or more parallel downloads, if you are willing to
go with 1kb/s).

-- 
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      ---==---(_)__  __ ____  __       Marc Lehmann      +--
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This archive was generated by hypermail 2b29 : Fri Aug 31 2001 - 21:00:18 EST