Date: Thu, 30 Dec 2010 09:57:23 +0100 From: Marco van Tol <marco@tols.org> To: freebsd-fs@freebsd.org Subject: Re: 8.2-RC1 and ZFS Message-ID: <20101230085723.GA38391@tolstoy.tols.org> In-Reply-To: <4D1BCE34.4090601@nw-ds.com> References: <4D1BCE34.4090601@nw-ds.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Dec 29, 2010 at 05:11:32PM -0700, David Samms wrote: > I gave ZFS a try again this afternoon and immediately came across what I > would consider a problem. Simply running dd causes such IO contention > that a GUI desktop is unusable and MP3s stop playing. The problem is > very repeatable, just run dd if=/dev/zero of=big bs=1m count=6400 > > System is amd64, source updated Dec 27. Default ZFS parameters. (no > tuning). With the same system but UFS+s dd causes no problems. Check out this mail from Jeremy Chadwick from December 28th in freebsd-stable@. http://docs.freebsd.org/cgi/getmsg.cgi?fetch=312384+0+current/freebsd-stable I think specifically the comments and tweaks regarding vfs.zfs.txg.timeout="5" and vfs.zfs.txg.write_limit_override=1073741824 should be usefull for you. :-) I'm intentionally not touching the subject why you see what you do without tuning. I'm sure there are a great bunch of different situations for which the defaults are the way they are. :-) Marco van Tol -- "Van Duitsers heb je pas gewonnen als ze met de bus de stad uit zijn." - Youp van 't Hek
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20101230085723.GA38391>