On Oct 03, 2002 16:34 -0700, Jay Thorne wrote: > ...what I'm writing to you about is kjournald. > > When this apparently looping state is reached, kjournald shows D > state for several seconds. During that same time, block-out "bo" in vmstat > consistently shows 0. kjournald is choking. Or something. Also, this appears > to get a lot of processes looping on write somewhere in the webserver. > Looping on the lockfile, maybe? The runqueue gets huge > 40 often , and > apache spirals up to all 75 processes in use. These pauses seem to occur at > pretty exact intervals. Something like every 240 seconds. With the disk in > question mounted as ext2 I don't get the issue. At all. > > I'd like to find a way to tell kjournald to wait less time with smaller > buffers so that the big pause while kjournald flushes and subsequent long > runqueue and its associated context switch overhead does not occur. In Linux's tradition of pre-emptive bug fixing, the parameter you seek was just added to the official 2.4.20-pre9 kernel announced yesterday. It allows you to specify the flush interval on a per-filesystem basis. Since sct submitted it, I assume it is also in the RH kernel, but probably only in a RawHide kernel and not an official errata kernel yet. Summary of changes from v2.4.20-pre8 to v2.4.20-pre9 ==================================================== : : <sct@redhat.com>: o 2.4.20-pre4/ext3: Bump ext3 version number o 2.4.20-pre4/ext3: Fix LVM snapshot deadlock o 2.4.20-pre4/ext3: jbd commit interval tuning o Sanity check for Intermezzo/ext3 o ext3 commit notification for Intermezzo o Fix the order of inodes being marked dirty in a couple of corner cases It appears that this patch is actually _not_ in the RH 12.5 kernel, but maybe there is a more recent RawHide kernel? If not, the patch is at: http://marc.theaimsgroup.com/?l=linux-kernel&m=103304960604993&w=4 Cheers, Andreas -- Andreas Dilger http://www-mddsp.enel.ucalgary.ca/People/adilger/ http://sourceforge.net/projects/ext2resize/ _______________________________________________ Ext3-users@redhat.com https://listman.redhat.com/mailman/listinfo/ext3-users
