From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44285) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eBg7P-0000kg-Am for qemu-devel@nongnu.org; Mon, 06 Nov 2017 07:03:08 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eBg7J-0005aB-JW for qemu-devel@nongnu.org; Mon, 06 Nov 2017 07:03:07 -0500 Received: from mx1.redhat.com ([209.132.183.28]:56940) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eBg7J-0005Zt-DS for qemu-devel@nongnu.org; Mon, 06 Nov 2017 07:03:01 -0500 References: <80415da5-4eef-bf85-b617-fadc3dae4475@redhat.com> <20171106115931.GB3898@lemon> From: Paolo Bonzini Message-ID: Date: Mon, 6 Nov 2017 13:02:50 +0100 MIME-Version: 1.0 In-Reply-To: <20171106115931.GB3898@lemon> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] qemu core file size List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: Wanpeng Li , Alexey Kardashevskiy , "qemu-devel@nongnu.org Developers" On 06/11/2017 12:59, Fam Zheng wrote: >>> Could you point out the patchset for the fix? >> Between 447b0d0b9ee8a0ac216c3186e0f3c427a1001f0c and >> 092aa2fc65b7a35121616aad8f39d47b8f921618. > Not sure how these relate to the core size, but I've tested upstream > (ec7a8bf0b8f7dc7288fe8745464ee8217528cc6c) and with dump-guest-core=off the core > file is 363M, still significantly larger than rss (~73M). > > What is bloating the core file? My guess would have been fragmented heap. The core file, unlike the RSS, includes all the mmaped memory (e.g. from shared libraries) that has never been used. For example, all the Ceph/Gluster/PulseAudio/SPICE/whatever libraries are included in the core file but likely are not in the RSS. Paolo