From owner-freebsd-questions Wed Oct 27 9:44:52 1999 Delivered-To: freebsd-questions@freebsd.org Received: from picnic.mat.net (picnic.mat.net [206.246.122.133]) by hub.freebsd.org (Postfix) with ESMTP id 44CDC14CD4; Wed, 27 Oct 1999 09:44:38 -0700 (PDT) (envelope-from chuckr@picnic.mat.net) Received: from localhost (chuckr@localhost [127.0.0.1]) by picnic.mat.net (8.9.3/8.9.3) with ESMTP id MAA15407; Wed, 27 Oct 1999 12:43:53 -0400 (EDT) (envelope-from chuckr@picnic.mat.net) Date: Wed, 27 Oct 1999 12:43:52 -0400 (EDT) From: Chuck Robey To: Ben Rosengart Cc: Chuck Youse , Ilia Chipitsine , questions@FreeBSD.ORG, hackers@FreeBSD.ORG Subject: Re: why FFS is THAT slower than EXT2 ? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, 27 Oct 1999, Ben Rosengart wrote: > On Wed, 27 Oct 1999, Chuck Robey wrote: > > > On Wed, 27 Oct 1999, Ben Rosengart wrote: > > > > > On Wed, 27 Oct 1999, Chuck Youse wrote: > > > > > > > One of the biggest reasons for the difference: FreeBSD, by default, > > > > performs _synchronous_ metadata updates, and Linux performs asynchronous > > > > metadata updates. > > > > > > > > It's definitely a bit slower, but the payoff is in reliability. I have > > > > seen more than one [production!] Linux machine completely trash its > > > > filesystems because the implementors decided that their "NT-killer" must > > > > have good performance at the expense of serious, production-quality > > > > reliability. > > > > > > Read the post again -- they were using soft updates. > > > > Why is that important? Soft updates is still far better than an async > > filesystem. Have you lost files in panics? I haven't. > > What panics? I've been running -stable and it's been living up to the > name. > > I was pointing out to Chuck Youse that BSD metadata writes are also > (mostly) asynchronous now, so if FFS is truly slower than ext2fs, there > must be some other reason. It felt like it was a comment on the filesystem reliability (the subject of the immediately preceding paragraph). I didn't see how softupdates hurt that reliability. > > -- > Ben Rosengart > > UNIX Systems Engineer, Skunk Group > StarMedia Network, Inc. > > ---------------------------------------------------------------------------- Chuck Robey | Interests include C programming, Electronics, 213 Lakeside Dr. Apt. T-1 | communications, and signal processing. Greenbelt, MD 20770 | I run picnic.mat.net: FreeBSD-current(i386) and (301) 220-2114 | jaunt.mat.net : FreeBSD-current(Alpha) ---------------------------------------------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message