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From: "David Schwartz" <davids@webmaster.com>
To: "Chuck Winters" <cwinters@atl.lmco.com>, <linux-kernel@vger.kernel.org>
Subject: RE: Number of File descriptors
Date: Fri, 13 Jul 2001 23:03:07 -0700
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> Hello All,
> 	My interest has been peaked by a recent email.  At one
> point, I heard two people speaking
> about how some database guy wanted to have 2000 open files(or
> something crazy like that).
> They said that he must be crazy because the kernel does a
> sequential search through the open
> file descriptors.  Anyway, I read a posting an a mail list that
> someone wanted select to
> select on 3000 files.  Alright, the question(Finally!):
> 		To have select() select on 3000 file descriptors,
> they must be open.  That's 3000 open
> 		files.  Will select be ultra slow trying to select
> on 3000 file descriptors?  Also,
> 		what is the clarification on the kernel doing a
> sequential search through the open
> 		file descriptors?

	Using 'select' on 3,000 file descriptors is not a problem. I have used
'poll' on 12,000 file descriptors with no problems at all. Performance is
not exactly stellar (you can use threads to improve it) but it's quite good.

	DS

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