Re: SD still better than CFS for 3d ?(was Re: 2.6.23-rc1)

Peter Zijlstra
2007-07-31T06:31:24Z

On Tue, 2007-07-31 at 01:46 +0200, Kasper Sandberg wrote:

> could perhaps be filesystem related, i have my maildir(extremely large)
> on reiserfs, and /home on xfs. what my mail client will do is download
> mail, spamasassin it(loading database from home), then it will put to
> imap server placing it on reiserfs, and then a "local" copy in my home.

Ooh, do you perchance have PREEMPT_BKL=y?

If so, try on another filesystem than reiserfs (or disable PREEMPT_BKL,
but that is obviously the lesser of the two choices).

Ingo traced a 1+ second latency at my end to BKL priority inversion
between tty and reiserfs.