Subject: Re: Limiting disk I/O?
To: Michael van Elst <>
From: Steven M. Bellovin <>
List: tech-kern
Date: 11/13/2007 00:18:17
On Mon, 12 Nov 2007 20:38:10 +0000 (UTC) (Michael van Elst) wrote:

> (Jukka Marin) writes:
> >Wow :-)  But I don't think delaying a catastrophe is the same as
> >preventing it :-)  I would like to slow down the sync operation (to
> >leave part of the I/O capacity for other things).  I guess I could
> >try making the delays real short and see what happens then..
> The problem comes from running out of buffers. You want to sync
> often and you want to sync fewer buffers in a burst to mitigate
> the problem.

This, I think, is a large part of the actual solution to the problem.
The other part is to have the process scheduler penalize processes -- or
users? -- that do too much I/O.

		--Steve Bellovin,