Even if max_hw_sectors_in=32767? -- Stuart Midgley Ph.D. Manager Production Services DownUnder GeoSolutions stua...@dugeo.com
On 18/04/2009, at 3:06, Andreas Dilger <adil...@sun.com> wrote: > On Apr 17, 2009 08:40 -0400, Robin Humble wrote: >> we have a similar problem. >> Lustre: short-OST0001: underlying device md0 should be tuned for >> larger I/O requests: max_sectors = 1024 could be up to >> max_hw_sectors=1280 >> >> sadly, that sys entry doesn't exist: >> cat: /sys/block/md0/queue/max_sectors_kb: No such file or directory >> >> do you have any other suggestions? >> perhaps the devices below md need looking at? >> they all report /sys/block/sd*/queue/max_sectors_kb == 512. >> we have an md raid6 8+2. > > Since MD RAID is really composed of underlying disks, and doing the > mapping from /dev/md0 -> /sys/block/sd* is difficult, mount.lustre > can't do the tuning itself. Instead, you should add a line into > /etc/init.d/rc.local like: > > for DEV in sdc sdl sdk sdj sdi sdh sdg sdf sde sdd; do > cp /sys/block/$DEV/queue/{max_hw_sectors_kb,max_sectors_kb} > done > >> uname -a >> Linux sox2 2.6.18-92.1.10.el5_lustre.1.6.6.fixR5 #2 SMP Wed Feb 4 >> 16:58:30 EST 2009 x86_64 x86_64 x86_64 GNU/Linux >> (which is 1.6.6 + the patch from bz 15428 which is (I think) now in >> 1.6.7.1) >> >> cat /proc/mdstat >> ... >> md0 : active raid6 sdc[0] sdl[9] sdk[8] sdj[7] sdi[6] sdh[5] sdg[4] >> sdf[3] sde[2] sdd[1] >> 5860595712 blocks level 6, 64k chunk, algorithm 2 [10/10] >> [UUUUUUUUUU] >> in: 64205147 reads, 97489370 writes; out: 3730773413 >> reads, 3281459807 writes >> 2222983790 in raid5d, 498868 out of stripes, 4280451425 >> handle called >> reads: 0 for rmw, 709671189 for rcw. zcopy writes: 1573400576 >> , copied writes: 20983045 >> 0 delayed, 0 bit delayed, 0 active, queues: 0 in, 0 >> out >> 0 expanding overlap >> >> cheers, >> robin >> _______________________________________________ >> Lustre-discuss mailing list >> Lustre-discuss@lists.lustre.org >> http://lists.lustre.org/mailman/listinfo/lustre-discuss > > Cheers, Andreas > -- > Andreas Dilger > Sr. Staff Engineer, Lustre Group > Sun Microsystems of Canada, Inc. > > _______________________________________________ > Lustre-discuss mailing list > Lustre-discuss@lists.lustre.org > http://lists.lustre.org/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list Lustre-discuss@lists.lustre.org http://lists.lustre.org/mailman/listinfo/lustre-discuss