From owner-freebsd-performance@FreeBSD.ORG Fri Feb 1 13:58:07 2008 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D539416A418; Fri, 1 Feb 2008 13:58:07 +0000 (UTC) (envelope-from prvs=1917699425=killing@multiplay.co.uk) Received: from mail1.multiplay.co.uk (core6.multiplay.co.uk [85.236.96.23]) by mx1.freebsd.org (Postfix) with ESMTP id 3E0D113C448; Fri, 1 Feb 2008 13:58:07 +0000 (UTC) (envelope-from prvs=1917699425=killing@multiplay.co.uk) DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=multiplay.co.uk; s=Multiplay; t=1201874238; x=1202479038; q=dns/txt; h=Received: Message-ID:From:To:Cc:References:Subject:Date:MIME-Version: Content-Type:Content-Transfer-Encoding; bh=ELQeJzXmQpJ6PKdXj5yTI KBtVxGm3CKtYQVKJwRgitk=; b=lquxXSELur70yJnO/eh0LxcBSpXdXKJZRTlN3 1uV/zWImFUYUJivGrgedHoB0z5RXoiMdM0BWXgjbHPLRrT7LnPPnWd3PYtFmWjeV s1YP9IucF6e+//F09nWG5vOU1feqHhC9Ge8ESsyQl8mU1QrRo5Qm3G/+vcLkSzk3 jYHDYI= X-Spam-Checker-Version: SpamAssassin 3.1.8 (2007-02-13) on mail1.multiplay.co.uk X-Spam-Level: X-Spam-Status: No, score=-14.7 required=6.0 tests=BAYES_00, USER_IN_WHITELIST, USER_IN_WHITELIST_TO autolearn=ham version=3.1.8 Received: from r2d2 by mail1.multiplay.co.uk (MDaemon PRO v9.6.3) with ESMTP id md50004973894.msg; Fri, 01 Feb 2008 13:57:15 +0000 Message-ID: <018701c864da$57020f20$b6db87d4@multiplay.co.uk> From: "Steven Hartland" To: "Steven Hartland" , "Eric Anderson" References: <200801310147.BAA04522@sopwith.solgatos.com><47A2A606.9080702@freebsd.org><002201c86499$7861ac20$b6db87d4@multiplay.co.uk><47A30EA7.7050506@freebsd.org> <016401c864d6$73251c50$b6db87d4@multiplay.co.uk> Date: Fri, 1 Feb 2008 13:57:09 -0000 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=response Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 X-Authenticated-Sender: Killing@multiplay.co.uk X-MDRemoteIP: 212.135.219.182 X-Return-Path: prvs=1917699425=killing@multiplay.co.uk X-Envelope-From: killing@multiplay.co.uk X-Spam-Processed: mail1.multiplay.co.uk, Fri, 01 Feb 2008 13:57:16 +0000 X-MDAV-Processed: mail1.multiplay.co.uk, Fri, 01 Feb 2008 13:57:18 +0000 Cc: Dieter , freebsd-performance@freebsd.org Subject: Re: newfs locks entire machine for 20seconds X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Feb 2008 13:58:07 -0000 ----- Original Message ----- From: "Steven Hartland" > ----- Original Message ----- > From: "Eric Anderson" >> Wait - if it returns EAGAIN for a while, then look at that code above. >> It will hold the sysctl lock for some indefinite amount of time. Maybe >> it should look like this instead: >> >> >> do { >> SYSCTL_LOCK(); >> req.oldidx = 0; >> req.newidx = 0; >> error = sysctl_root(0, name, namelen, &req); >> SYSCTL_UNLOCK(); >> } while (error == EAGAIN); >> >> if (req.lock == REQ_WIRED && req.validlen > 0) >> vsunlock(req.oldptr, req.validlen); >> > > Tried no difference unfortunately, possibly its give the closeness > of the lock unlock its just reacquiring the lock straight after releasing > it hence not giving the other thread chance to run / obtain the lock? In an attempt to prove this is in fact the issue I've tried with the locking around this code removed, yes dangerous but just as a test :) It does indeed prevent the extended lockup so this is the right area. Regards Steve ================================================ This e.mail is private and confidential between Multiplay (UK) Ltd. and the person or entity to whom it is addressed. In the event of misdirection, the recipient is prohibited from using, copying, printing or otherwise disseminating it or any information contained in it. In the event of misdirection, illegible or incomplete transmission please telephone +44 845 868 1337 or return the E.mail to postmaster@multiplay.co.uk.