From owner-freebsd-current@FreeBSD.ORG Tue May 3 13:59:10 2005 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from green.homeunix.org (freefall.freebsd.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id BA9B216A4CE; Tue, 3 May 2005 13:59:09 +0000 (GMT) Received: from green.homeunix.org (green@localhost [127.0.0.1]) by green.homeunix.org (8.13.3/8.13.1) with ESMTP id j43Dx68O082029; Tue, 3 May 2005 09:59:06 -0400 (EDT) (envelope-from green@green.homeunix.org) Received: (from green@localhost) by green.homeunix.org (8.13.3/8.13.1/Submit) id j43Dx59F082028; Tue, 3 May 2005 09:59:05 -0400 (EDT) (envelope-from green) Date: Tue, 3 May 2005 09:59:05 -0400 From: Brian Fundakowski Feldman To: Marc Olzheim Message-ID: <20050503135905.GA77223@green.homeunix.org> References: <20050426140701.GB5789@green.homeunix.org> <20050426151751.GB68038@stack.nl> <20050426155043.GC5789@green.homeunix.org> <20050426160609.GA68511@stack.nl> <20050426162549.GD5789@green.homeunix.org> <20050426164346.GA68763@stack.nl> <20050426193602.GE5789@green.homeunix.org> <20050427081746.GA66441@stack.nl> <20050427160857.GF5789@green.homeunix.org> <20050503094700.GA65878@stack.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050503094700.GA65878@stack.nl> User-Agent: Mutt/1.5.6i cc: freebsd-current@freebsd.org cc: freebsd-stable@freebsd.org Subject: Re: NFS client/buffer cache deadlock X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 May 2005 13:59:10 -0000 On Tue, May 03, 2005 at 11:47:00AM +0200, Marc Olzheim wrote: > On Wed, Apr 27, 2005 at 12:08:57PM -0400, Brian Fundakowski Feldman wrote: > > Alright, this will do synchronous, instead of short, writes (also, > > of course, not deadlock the system) if you are trying to use an > > excessively large buffer size. > > > > > > > > Will this be incorporated in time for 5.4 ? It really needs someone else to review the code changes more than just conceptually to make this kind of an adjustment before release. It is not truly an optimal solution, as fully synchronous writes are not necessary; just limiting the "write window" size and requiring posted transactions to complete before queueing up more is. Doing that is more error-prone, however, and would I think complicate things just to optimize the speed of a rare case. Still, there are probably a few who would object, in which case they should do the work of optimizing that side case ;) There's still missing an actual mount_nfs(8) configuration flag and documentation, but those things are trivial. (Forwarded on to -current as well, for additional eyes/testers.) -- Brian Fundakowski Feldman \'[ FreeBSD ]''''''''''\ <> green@FreeBSD.org \ The Power to Serve! \ Opinions expressed are my own. \,,,,,,,,,,,,,,,,,,,,,,\