From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752686AbaCXJnf (ORCPT ); Mon, 24 Mar 2014 05:43:35 -0400 Received: from e28smtp04.in.ibm.com ([122.248.162.4]:33947 "EHLO e28smtp04.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751556AbaCXJnd (ORCPT ); Mon, 24 Mar 2014 05:43:33 -0400 Message-ID: <532FFE3A.9060002@linux.vnet.ibm.com> Date: Mon, 24 Mar 2014 15:13:22 +0530 From: Janani Venkataraman User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Phillip Susi , Karel Zak CC: amwang@redhat.com, rdunlap@xenotime.net, andi@firstfloor.org, aravinda@linux.vnet.ibm.com, hch@lst.de, mhiramat@redhat.com, jeremy.fitzhardinge@citrix.com, xemul@parallels.com, suzuki@linux.vnet.ibm.com, kosaki.motohiro@jp.fujitsu.com, adobriyan@gmail.com, tarundsk@linux.vnet.ibm.com, vapier@gentoo.org, roland@hack.frob.com, tj@kernel.org, ananth@linux.vnet.ibm.com, gorcunov@openvz.org, avagin@openvz.org, oleg@redhat.com, eparis@redhat.com, d.hatayama@jp.fujitsu.com, james.hogan@imgtec.com, akpm@linux-foundation.org, torvalds@linux-foundation.org, coreutils@gnu.org, procps@freelists.org, util-linux@vger.kernel.org, util-linux@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 00/33] [RFC] Non disruptive application core dump infrastructure References: <20140320093040.14878.903.stgit@localhost.localdomain> <20140321080855.GE26374@x2.net.home> <532C54A3.3030903@ubuntu.com> In-Reply-To: <532C54A3.3030903@ubuntu.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14032409-5564-0000-0000-00000CA5473C Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/21/2014 08:32 PM, Phillip Susi wrote: > On 3/21/2014 4:17 AM, Karel Zak wrote: >> The gencore command looks like a good idea, but why we need the >> client-server infrastructure? At least at first glance it seems >> like overkill. > Yes, the server seems pointless. > >>> We would like to push this to one of the following packages: a) >>> util-linux b) coreutils c) procps-ng >> d) somewhere near to gdb :-) > gdb already has such a thing; it's called gcore. Kind of makes this > work seem redundant? Gcore attaches to the process using gdb and runs the gdb gcore command and then detaches. In gcore the dump cannot be issued from a signal handler context as fork() is not signal safe and moreover it is disruptive in nature as the gdb attaches using ptrace which sends a SIGSTOP signal. Hence the gcore method cannot be used if the process wants to initiate a self dump as well. The following link points to a discussion regarding why not gcore. https://lkml.org/lkml/2013/9/3/122 >