When the volume is slugish do you see lots of tiny reads (500k/sec) on the full volume? When it slows down could you run an "iostat -k 2" on the OSS in question? I think we may be having the same problem. I could find no answer/solution and ended up blowing the whole setup away and starting from scratch. I'd like to track this down and figure out if its actually a bug or whether I FUBAR'd something in my setup.
-Aaron On Dec 25, 2007, at 9:42 AM, Balagopal Pillai wrote: > Hi, > > Please ignore the previous email. It seemed to solve itself > after 10 > - 15 minutes of mounting the filled volume. Now it is as fast as the > empty > volumes. > > Thanks > Balagopal > > ---------- Forwarded message ---------- > Date: Tue, 25 Dec 2007 10:36:28 -0400 (AST) > From: Balagopal Pillai <[EMAIL PROTECTED]> > To: <[email protected]> > Subject: lustre performance question > > Hi, > > We have one Lustre volume that is getting full and some other > volumes that are totally empty. The one that is full is a little > sluggish > at times with the following messages appearing in syslog on the OSS - > > Lustre: 5809:0:(filter_io_26.c:698:filter_commitrw_write()) data1- > OST0001: > slow i_mutex 82s > Lustre: 5809:0:(filter_io_26.c:711:filter_commitrw_write()) data1- > OST0001: > slow brw_start 82s > Lustre: 5809:0:(filter_io_26.c:763:filter_commitrw_write()) data1- > OST0001: > slow direct_io 82s > Lustre: 5809:0:(filter_io_26.c:776:filter_commitrw_write()) data1- > OST0001: > slow commitrw commit 82s > > But the same two OSS are also exporting the empty volume, > which > is very fast on any tests (like creation of a tar file, bonnie etc > etc) > I also tested the same thing on the nfs exported backup volume of the > filled up lustre volume (exported from the same OSS server) and it > doesn't > show any significant slow down. Is it normal for Lustre volumes to > slow > down when the volumes get full? > > Thanks > Balagopal > > _______________________________________________ > Lustre-discuss mailing list > [email protected] > https://mail.clusterfs.com/mailman/listinfo/lustre-discuss Aaron Knister Associate Systems Analyst Center for Ocean-Land-Atmosphere Studies (301) 595-7000 [EMAIL PROTECTED] _______________________________________________ Lustre-discuss mailing list [email protected] https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
