From owner-freebsd-hackers Wed Oct 27 9:45:29 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from chuggalug.clues.com (chuggalug.clues.com [194.217.82.22]) by hub.freebsd.org (Postfix) with ESMTP id 0EF001542A; Wed, 27 Oct 1999 09:45:20 -0700 (PDT) (envelope-from geoffb@chuggalug.clues.com) Received: (from geoffb@localhost) by chuggalug.clues.com (8.9.3/8.9.3) id RAA99444; Wed, 27 Oct 1999 17:44:54 +0100 (BST) (envelope-from geoffb) Date: Wed, 27 Oct 1999 17:44:54 +0100 From: Geoff Buckingham To: Ben Rosengart Cc: Chuck Robey , Chuck Youse , Ilia Chipitsine , questions@FreeBSD.ORG, hackers@FreeBSD.ORG Subject: Re: why FFS is THAT slower than EXT2 ? Message-ID: <19991027174454.A99169@chuggalug.clues.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: ; from Ben Rosengart on Wed, Oct 27, 1999 at 12:44:42PM -0400 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, Oct 27, 1999 at 12:44:42PM -0400, 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. > I heard talk the linux folks where using btrees to better handle large directories. -- GeoffB To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message