From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (mx1.redhat.com [172.16.48.31]) by int-mx1.corp.redhat.com (8.12.11.20060308/8.12.11) with ESMTP id k6SEMxpf020069 for ; Fri, 28 Jul 2006 10:22:59 -0400 Received: from nexredback-216-168-119-94.nexicom.net (mail.fibrespeed.net [216.168.105.35] (may be forged)) by mx1.redhat.com (8.12.11.20060308/8.12.11) with SMTP id k6SEMuML022848 for ; Fri, 28 Jul 2006 10:22:56 -0400 Message-ID: <44CA1DB7.10609@mikebabcock.ca> Date: Fri, 28 Jul 2006 10:22:47 -0400 From: "Michael T. Babcock" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [linux-lvm] Performance impact of LVM References: <20060727120250.GB17454@freshdot.net> <44C8DC2D.3000408@conterra.de> In-Reply-To: Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: LVM general discussion and development Mark H. Wood wrote: > However this effect is probably down in the noise for most systems. > The only way to know if it's a problem for you is to measure. I would > expect that, given contemporary amounts of caching on the drive, the > controller, and in the OS, you probably won't see it unless you are > driving your storage *really* hard. If you do, dump/recreate > contiguously/restore will make it go away. For database partitions we always use "lvcreate -C y" when creating LVs for this reason, for every other area of the system however, I haven't noticed almost any impact of LVM(1 or 2) except that striping is easier to set up than using RAID0 because there's no need to repartition. For example, I often do something like: lvcreate -C y -n dbdata1 -L 100G mainstore lvcreate -I 2 -n dbtemp -L 10G mainstore