Date: Thu, 13 Nov 2003 14:29:21 +0100 (CET) From: Martin Blapp <mb@imp.ch> To: Allen Briggs <briggs@wasabisystems.com> Cc: freebsd-scsi@freebsd.org Subject: Re: Very bad FreeBSD SCSI RAID5 write speed performance Message-ID: <20031113142735.S13503@cvs.imp.ch> In-Reply-To: <20031113132327.GF13029@canolog.ninthwonder.com> References: <20031112172306.J4572@pooker.samsco.home> <20031113084355.P13503@cvs.imp.ch> <20031113132327.GF13029@canolog.ninthwonder.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Hi, > On Thu, Nov 13, 2003 at 06:38:53AM -0500, Gary Stanley wrote: > > root@64:[/tmp/blah]>dd if=/dev/zero of=/tmp/blah/blah > > 89472+0 records in > > 89471+0 records out > > 45809152 bytes transferred in 8.546312 secs (5360108 bytes/sec) Exactly what we get here: ~ 6MB per second with RAID5 and the IPS driver. The Adaptec 3200s is similar. A single disk has writes to the 53MB to the raw slice. I don't know why 5 equal disks on 2 busses are that slow. Martin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20031113142735.S13503>