From owner-freebsd-stable@FreeBSD.ORG Sat Oct 4 14:58:43 2014 Return-Path: Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 12D1C2CE; Sat, 4 Oct 2014 14:58:43 +0000 (UTC) Received: from smtp1.multiplay.co.uk (smtp1.multiplay.co.uk [85.236.96.35]) by mx1.freebsd.org (Postfix) with ESMTP id CA786CAE; Sat, 4 Oct 2014 14:58:42 +0000 (UTC) Received: by smtp1.multiplay.co.uk (Postfix, from userid 65534) id CB20020E7089B; Sat, 4 Oct 2014 14:58:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.multiplay.co.uk X-Spam-Level: * X-Spam-Status: No, score=1.6 required=8.0 tests=AWL,BAYES_00,DOS_OE_TO_MX, FSL_HELO_NON_FQDN_1,RDNS_DYNAMIC,STOX_REPLY_TYPE autolearn=no version=3.3.1 Received: from r2d2 (82-69-141-170.dsl.in-addr.zen.co.uk [82.69.141.170]) by smtp1.multiplay.co.uk (Postfix) with ESMTP id 7C71120E70899; Sat, 4 Oct 2014 14:58:40 +0000 (UTC) Message-ID: <6618E7E0B17D41D09DB9B0160C2D4DF1@multiplay.co.uk> From: "Steven Hartland" To: "Glen Barber" References: <20141004024011.GC1199@hub.FreeBSD.org> <64F0D761D09546C7B47DFAA1551500BE@multiplay.co.uk> <20141004031614.GD1199@hub.FreeBSD.org> Subject: Re: Heads-up: Possible regression between 10.0-RELEASE and 10.1-BETA1 with '/ on ZFS' setup Date: Sat, 4 Oct 2014 15:58:35 +0100 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 Cc: FreeBSD Release Engineering Team , freebsd-stable@FreeBSD.org X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Oct 2014 14:58:43 -0000 ----- Original Message ----- From: "Glen Barber" > On Sat, Oct 04, 2014 at 03:51:39AM +0100, Steven Hartland wrote: > > > [...] > > >A possible solution to this is to set kern.kstack_pages=4 via loader(8), > > >however in my tests (solely in VirtualBox), this has been ineffective. > > > > > > > This has been a known issue on i386 since the switch to Clang see UPDATING: > > 20121223: > > After switching to Clang as the default compiler some users of ZFS > > on i386 systems started to experience stack overflow kernel panics. > > Please consider using 'options KSTACK_PAGES=4' in such configurations. > > > > In my experience your millage may vary but essentially without 4 stack pages > > all bets are off in terms of stability. > > > > Did you read my email? Cleary 4am was too late to be reading emails and my brain didn't ingest the "has been ineffective" so sorry for that. That said setting options KSTACK_PAGES=4 has more reaching effects than kern.kstack_pages=4 so I wonder if you recompiled the kernel with this option if you would have any more luck? Regards Steve