From owner-freebsd-hackers@FreeBSD.ORG Tue Apr 1 05:17:50 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6589637B405 for ; Tue, 1 Apr 2003 05:17:50 -0800 (PST) Received: from comp.chem.msu.su (comp-ext.chem.msu.su [158.250.32.157]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4987243F85 for ; Tue, 1 Apr 2003 05:17:45 -0800 (PST) (envelope-from yar@comp.chem.msu.su) Received: from comp.chem.msu.su (localhost [127.0.0.1]) by comp.chem.msu.su (8.12.3p2/8.12.3) with ESMTP id h31DGHhE012567; Tue, 1 Apr 2003 17:17:38 +0400 (MSD) (envelope-from yar@comp.chem.msu.su) Received: (from yar@localhost) by comp.chem.msu.su (8.12.3p2/8.12.3/Submit) id h31DGGCC012566; Tue, 1 Apr 2003 17:16:16 +0400 (MSD) (envelope-from yar) Date: Tue, 1 Apr 2003 17:16:16 +0400 From: Yar Tikhiy To: Poul-Henning Kamp Message-ID: <20030401131616.GA11282@comp.chem.msu.su> References: <20030401123319.GA8399@comp.chem.msu.su> <32984.1049200665@critter.freebsd.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <32984.1049200665@critter.freebsd.dk> User-Agent: Mutt/1.5.3i cc: hackers@freebsd.org Subject: Re: "Expensive timeout(9) function..." X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 01 Apr 2003 13:17:50 -0000 On Tue, Apr 01, 2003 at 02:37:45PM +0200, Poul-Henning Kamp wrote: > In message <20030401123319.GA8399@comp.chem.msu.su>, Yar Tikhiy writes: > >Hello, > > > >I'm getting the following DIAGNOSTIC messages on my -CURRENT box: > > > > Expensive timeout(9) function: 0xc02677e0(0) 0.006095064 s > > > >(it's uma_timeout(), which triggers the warning once per boot) > > > > Expensive timeout(9) function: 0xc0141610(0xc0dfcc00) 0.006581587 s > > Expensive timeout(9) function: 0xc0141610(0xc0dfcc00) 0.008510173 s > > > >(and this one is fxp_tick(); it triggers the warning from time to time) > > > >Are those warnings harmless? > > Yes, but indicative of code which needs attention, but harmless. > > >As far as my understanding of the issue reaches, a timeout function > >is called under protection of the Giant mutex unless it's marked > >as MP-safe, and that's the reason to spend as little time as possible > >in it. Right? > > Yes, but there are other reasons why you would generally not want > to spend too much time in the timeout function, mostly that it may > screw up other time-critical things in the system. Thanks for your explanation! I hope this little thread will draw the attention of the responsible or interested parties to the warnings ;-) -- Yar