From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <000e01c36bf9$e5f82720$6402000a@gasaraki> From: "Henric Andersson" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [linux-lvm] Poor performance with LVM 1.0.7 Sender: linux-lvm-admin@sistina.com Errors-To: linux-lvm-admin@sistina.com Reply-To: linux-lvm@sistina.com List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: Date: Tue Aug 26 12:47:01 2003 List-Id: Content-Type: text/plain; charset="us-ascii" To: linux-lvm@sistina.com 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). 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). 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... /Henric