From owner-freebsd-current@FreeBSD.ORG Tue Mar 21 23:21:28 2006 Return-Path: X-Original-To: current@freebsd.org Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A0A2B16A401 for ; Tue, 21 Mar 2006 23:21:28 +0000 (UTC) (envelope-from jasone@freebsd.org) Received: from lh.synack.net (lh.synack.net [204.152.188.37]) by mx1.FreeBSD.org (Postfix) with ESMTP id D277F43D62 for ; Tue, 21 Mar 2006 23:21:24 +0000 (GMT) (envelope-from jasone@freebsd.org) Received: by lh.synack.net (Postfix, from userid 100) id 6D2005E4904; Tue, 21 Mar 2006 15:21:24 -0800 (PST) Received: from [129.101.167.146] (unknown [129.101.167.146]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by lh.synack.net (Postfix) with ESMTP id 14B7A5E48DE; Tue, 21 Mar 2006 15:21:23 -0800 (PST) In-Reply-To: <20060321222046.GY35129@funkthat.com> References: <20060321184019.GX35129@funkthat.com> <47CC5AC0-1B44-4485-92A9-70751681A527@freebsd.org> <20060321222046.GY35129@funkthat.com> Mime-Version: 1.0 (Apple Message framework v746.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <1EB2EEE3-855C-4B76-81A6-1880526797CE@freebsd.org> Content-Transfer-Encoding: 7bit From: Jason Evans Date: Tue, 21 Mar 2006 15:22:01 -0800 To: John-Mark Gurney X-Mailer: Apple Mail (2.746.2) X-Spam-Checker-Version: SpamAssassin 3.0.5 (2005-11-28) on lh.synack.net X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=none autolearn=failed version=3.0.5 Cc: current@freebsd.org Subject: Re: core dumps are HUGE... X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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, 21 Mar 2006 23:21:28 -0000 On Mar 21, 2006, at 2:20 PM, John-Mark Gurney wrote: > Jason Evans wrote this message on Tue, Mar 21, 2006 at 14:16 -0800: >> The core dump from the static binary is probably much smaller because >> nothing ever calls malloc (no dynamic loader in the mix). > > Ummm. you made the same mistake someone else did... The core dump > from the static binary is not smaller, it's much larger.. Reread > above... Okay then, invert the argument: The core dump from the dynamic binary is probably much smaller because rtld never calls the libc malloc. > And yes, I'm pretty sure that I have a world from before your > reduction > in chunk size... Having a minimum of a 6meg core doesn't sound like a > good idea... It's definately not going to play nice with small > systems.. I don't think that a 6 MB core file is the big deal you are making it out to be. A 50 MB core file is a pain, mainly because it takes a long time to dump core. Even so, consider that core dumps on OS X are in excess of 90 MB, and that this hasn't caused the world to stop revolving (though we should blame OS X for global warming). If this is of real concern to you though, you might consider looking into modifying the dump code to leave holes in the core file for unmapped pages when dumping to UFS. The vast majority of the core file is untouched pages in your simple test case. I was actually surprised to find that dumping doesn't appear to do this. Jason