Quoting Herbert Poetzl <herbert@13thfloor.at>: > On Fri, Jun 13, 2003 at 05:20:27PM -0700, Petro wrote: > > On Fri, Jun 13, 2003 at 01:55:01AM +0200, Herbert Poetzl wrote: > > > On Thu, Jun 12, 2003 at 03:28:59PM +0200, Koch, Steffen wrote: > > > > If someone has a solution for this please help. > > > hmm, do you have himem enabled (in kernel config)? > > > if yes, try to disable it ... > > > > Does this apply to RAID 0 as well? > > > > I've got several boxes running with: > > > > CONFIG_HIGHMEM4G=y > > # CONFIG_HIGHMEM64G is not set > > CONFIG_HIGHMEM=y > > > > And 2-4 GiB of ram under 2.4.18, with LVM 1.03. > > > > I'm trying to get LVM 1.07 to compile with 2.4.21 with : > > > > CONFIG_HIGHMEM4G=y > > # CONFIG_HIGHMEM64G is not set > > CONFIG_HIGHMEM=y > > CONFIG_HIGHIO=y > > > > > > Why is this bad? > > didn't say that this would be bad, only that > it live-locked my system at high load ... > the tenor on the list was: "highmem is bad" > so I turned it off, and, voila the system was > stable again ... snapshots + md + highmem is very bad if you don't use snapshots its perfectly OK > another, yet unexplained issue, is that on > another system, 4 SCSI discs, form a RAID 5 > array (software) which gives about 35MB > throughput, but lvm 1.0.7 ontop of that md > only has about 18MB throughput ... I've a bit defferent figures from a onboard HPT374 4 ide chanels with 4 IBM deskstars 80Gb, but i still lose 8-15Mb/s compared to plain md : /dev/hda: Timing buffer-cache reads: 128 MB in 0.41 seconds =308.43 MB/sec Timing buffered disk reads: 64 MB in 1.42 seconds = 45.07 MB/sec [root@svetljo root]# hdparm -tT /dev/md13 /dev/md13: Timing buffer-cache reads: 128 MB in 0.41 seconds =316.05 MB/sec Timing buffered disk reads: 64 MB in 1.08 seconds = 59.26 MB/sec [root@svetljo root]# hdparm -tT /dev/data data data2 [root@svetljo root]# hdparm -tT /dev/data2/Movies /dev/data2/Movies: Timing buffer-cache reads: 128 MB in 0.41 seconds =316.05 MB/sec Timing buffered disk reads: 64 MB in 1.32 seconds = 48.30 MB/sec time dd if=/dev/zero of=/mnt/Movies/BigFile.tm bs=1M count=4000 4000+0 records in 4000+0 records out 0.02user 15.57system 1:37.10elapsed 16%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (148major+40minor)pagefaults 0swaps best, Svetljo _______________________________________________ linux-lvm mailing list linux-lvm@sistina.com http://lists.sistina.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
