* Peter Zijlstra <[EMAIL PROTECTED]> wrote: > 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.
ah, indeed, that makes quite a bit of sense. Almost all of the Reiser3 code runs under the BKL, and the only other major kernel infrastructure that has BKL dependencies is the TTY code. Kasper, as a debugging matter, could you try to move that spamassassin workload off into a non-Reiser3 filesystem and/or disable PREEMPT_BKL? If that makes a noticeable difference (for the better ;) then we can continue figuring out what's happening exactly. Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/