Date: Mon, 22 Jun 2015 13:58:19 -0500 (CDT) From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us> To: kpneal@pobox.com Cc: freebsd-fs@freebsd.org Subject: Re: ZFS raid write performance? Message-ID: <alpine.GSO.2.01.1506221355420.12519@freddy.simplesystems.org> In-Reply-To: <20150622153056.GA96798@neutralgood.org> References: <5587C3FF.9070407@sneakertech.com> <20150622121343.GB60684@neutralgood.org> <55880544.70907@multiplay.co.uk> <20150622153056.GA96798@neutralgood.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, 22 Jun 2015, kpneal@pobox.com wrote: > Reading and writing to a raidz* requires touching all or almost all of > the disks. > > Writing to a mirror requires touching all the disks. Reading from a mirror > requires touching one disk. Keep in mind that for the same number of disks, using mirrors results in more vdevs and less use of precious IOPS. Also, using mirrors results in larger I/O requests since zfs blocks don't need to be fragmented. Bob -- Bob Friesenhahn bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?alpine.GSO.2.01.1506221355420.12519>