From owner-freebsd-hackers Wed Mar 22 22:09:19 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id WAA00470 for hackers-outgoing; Wed, 22 Mar 1995 22:09:19 -0800 Received: from Root.COM (implode.Root.COM [198.145.90.1]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id WAA00464 for ; Wed, 22 Mar 1995 22:09:16 -0800 Received: from corbin.Root.COM (corbin.Root.COM [198.145.90.18]) by Root.COM (8.6.8/8.6.5) with ESMTP id WAA05009; Wed, 22 Mar 1995 22:09:02 -0800 Received: from localhost (localhost [127.0.0.1]) by corbin.Root.COM (8.6.11/8.6.5) with SMTP id WAA00166; Wed, 22 Mar 1995 22:09:02 -0800 Message-Id: <199503230609.WAA00166@corbin.Root.COM> X-Authentication-Warning: corbin.Root.COM: Host localhost didn't use HELO protocol To: Peter da Silva cc: terry@cs.weber.edu, hasty@star-gate.com, hackers@FreeBSD.org Subject: Re: Why IDE is bad In-reply-to: Your message of "Wed, 22 Mar 95 23:35:37 CST." <199503230535.XAA04934@bonkers.taronga.com> From: David Greenman Reply-To: davidg@Root.COM Date: Wed, 22 Mar 1995 22:09:01 -0800 Sender: hackers-owner@FreeBSD.org Precedence: bulk >> It should do what the manual page says it does, which is to force all I/O >> to the filesystem to be done asynchronously. > >Um, all I/O to the file system is already done asynchronously. It's got >internal sequencing of metadata but that shouldn't be visible to the >process. It's the metadata I/O that we're talking about. ...and yes, the process will definately see it if the operation involves lots of file creates. It is inherently unsafe to do metadata I/O asynchronously, which is why the manual page says: async All I/O to the file system should be done asynchronously. This is a dangerous flag to set, and should not be used unless you are prepared to recreate the file system should your system crash. -DG