On Tue, Aug 26, 2003 at 07:45:54PM +0200, Henric Andersson wrote: > Hi all! > > I've recently upgraded my poor little fileserver from an old P120 Classic to > a brandspanking new Celeron 2Ghz with 512MB DDR memory. By doing this, I > expected the performance of my fileserver to increase, giving me a total of > 9,5MB/s when using samba. > > And it did. But not when LVM is concerned :( > > I have a VG setup with 3 drives (120GB each, not striped) which contains one > LV running an ext3 filesystem. > At first, I blamed my promise controllers (PDC 20269, ATA/133) but after > some serious testing, I found that whenever I didn't access files that was > stored on the LV, my speed was about 9.5MB/s, but when I transfered the same > file from the LV, I only got about half of it (4.2MB/s). The file I > transfered was roughly about 700-800MB big (same file used in all tests). check the raw performance of one drive involved with hdparm -tT ... > After scouring the net for suggestions on how to improve the speed, I came > up empty, and thus, I'm writing this email :) > > Some more facts (more available if needed ;)) about the server: > > All drives are tuned with 32bit transfers and DMA enabled. I'm running > kernel 2.4.22pre2 (gentoo). just for the fun of doing it, compile vanilla 2.4.22 and give it a try ... you could also add the following lvm patch ... http://www.13thfloor.at/VServer/patches-2.4.22-p10c17/07_lvm-1.0.7-2.4.21pre5.patch.bz2 > CPU usage is low (around 10-25%) when transfering files, so it does not seem > to be the bottleneck. > > Any suggestions and/or ideas are welcomed... was the performance you had on your old box higher? or did you just expect an increase in speed, which didn't happen? best, Herbert > /Henric > > > _______________________________________________ > 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/ _______________________________________________ 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/
