From owner-freebsd-questions Wed Oct 27 9:30:21 1999 Delivered-To: freebsd-questions@freebsd.org Received: from acl.lanl.gov (acl.lanl.gov [128.165.147.1]) by hub.freebsd.org (Postfix) with ESMTP id 1E03A15401; Wed, 27 Oct 1999 09:30:16 -0700 (PDT) (envelope-from rminnich@lanl.gov) Received: from localhost (rminnich@localhost) by acl.lanl.gov (8.8.8/8.8.5) with ESMTP id KAA677849; Wed, 27 Oct 1999 10:29:54 -0600 (MDT) X-Authentication-Warning: acl.lanl.gov: rminnich owned process doing -bs Date: Wed, 27 Oct 1999 10:29:54 -0600 From: "Ronald G. Minnich" To: Chuck Youse Cc: 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, 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. To put it slightly more strongly: as far as I'm concerned ext2 is not a serious fs if you really care about handling power failures and other such fun things. In clusters as small as 64 machines I've measured a 5% probability that after a power failure one of the 64 ext2 file systems will have a trashed root file system. With freebsd, over a four-year span, running through lots of power outages, I didn't lose an FFS file system even *once* (except for the disk that burned up, but not even FFS can fix that one). ext2 needs a lot of help. Evidently it will be getting it soon, though. ron To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message