Date: Sun, 17 Feb 2002 11:10:31 -0500 From: Bill Moran <wmoran@potentialtech.com> To: Thomas Schuerger <schuerge@wjpserver.CS.Uni-SB.DE> Cc: freebsd-questions@FreeBSD.ORG Subject: Re: New dir layout structure slow on full disks? Message-ID: <3C6FD5F7.7060702@potentialtech.com> References: <200202171543.g1HFhVo26442@wjpserver.cs.uni-sb.de>
next in thread | previous in thread | raw e-mail | index | archive | help
Thomas Schuerger wrote: > Hi! > > I'm using 4.5-RELEASE and am quite happy with the new directory layout > stuff. It really speeds up file scans etc. a lot. > > But there can be serious performance loss: > > When a disk is nearly full (e.g. 98%, but still 1,6 GB free, values > taken from "df"), creating files becomes very slow. I noticed this > when I wanted to install a big port (e.g. kdebase2). The extraction of > the .tar.gz archive took really long and made my system more or less > unusable. tar took something like 90-99% system time for 3 minutes. Err ... have you compared this to performance on a filesystem that's close to full with the old dirpref code? I'm gussing it would be similarly slow. ffs doesn't run well with close-to-full drives, it was never intended to. I believe both the man pages for newfs and tunefs state that performance drops exponentially on a filesystem as it passes the 92% capacity mark. That's why, under normal conditions, only root can fill it beyond that mark. When you say 98% full, do you mean 98% of the 92%, or do you mean 98% of the total fs capacity? If the former is the case, then you really do have an issue that needs looked at. If the latter is the case, then you are simply reiterating a known limitation of ffs that's been there since (I believe) BSD 4.2. -- Bill Moran Potential Technology http://www.potentialtech.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3C6FD5F7.7060702>