From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33374) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z7ftv-0008Q4-TB for qemu-devel@nongnu.org; Wed, 24 Jun 2015 04:19:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z7ftr-0004Mq-Og for qemu-devel@nongnu.org; Wed, 24 Jun 2015 04:19:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58278) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z7ftr-0004MI-Aa for qemu-devel@nongnu.org; Wed, 24 Jun 2015 04:19:15 -0400 Date: Wed, 24 Jun 2015 09:19:10 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20150624081910.GA2206@work-vm> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] Migration issue with 4.0.x List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Andrey Korolyov Cc: Paolo Bonzini , "qemu-devel@nongnu.org" , "Michael S. Tsirkin" * Andrey Korolyov (andrey@xdel.ru) wrote: > Hello, > > during tests against 4.0.5/4.0.6 for the problem described in > https://lists.gnu.org/archive/html/qemu-devel/2015-06/msg03117.html I > had noticed another weird issue: VM hangs after a couple of minutes > after being migrated if the hypervisor is running mentioned kernel > version. It does not matter for workload type during migration (idle > VM hangs too) or memory configuration of the VM - I can type > characters in the shell but dmesg listing takes about a minute to be > displayed (as well as other I/O operations lilke ls). The main visible > symptom is that I`ve not able to launch 'top' just after migration - > it 'hangs' after reading its own pid stats: Radim fixed a bug that was causing me a post migration hang, I'm not sure if it's the same case though, worth trying the patch here: http://article.gmane.org/gmane.comp.emulators.kvm.devel/136607 Dave > > 0.000058 read(4, "2436 (bash) S 2434 2436 2436 34817 2514 4202752 > 4321 9165 0 3 0 13 0 6 20 0 1 0 55138 20561920 1045 > 18446744073709551615 4194304 5130324 140723572820800 140723572819456 > 139788860395630 0 65536 3686404 1266761467 0 0 0 17 0 0 0 0 0 0 > 7228872 7264912 17436672 140723572821400 140723572821406 > 140723572821406 140723572821998 0\n", 4095) = 324 > 0.000096 close(4) = 0 > 0.000061 open("/proc/2436/statm", O_RDONLY) = 4 > 0.000061 read(4, "5020 1045 755 229 0 293 0\n", 4095) = 26 > 0.000052 close(4) = 0 > 0.000053 brk(0x15da000) = 0x15da000 > 0.000074 stat("/proc/2514", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0 > 0.000083 open("/proc/2514/stat", O_RDONLY) = 4 > 0.000065 read(4, "2514 (strace) S 2436 2514 2436 34817 2514 > 4202496 107 0 0 0 0 0 0 0 20 0 1 0 64452 4546560 124 > 18446744073709551615 4194304 4502860 140732305872800 140732305872152 > 139895671099674 0 0 3166215 0 0 0 0 17 4 0 0 0 0 0 6600016 6601324 > 9408512 140732305878369 140732305878401 140732305878401 > 140732305879016 0\n", 4095) = 305 > 0.000094 close(4) = 0 > 0.000062 open("/proc/2514/statm", O_RDONLY) = 4 > 0.000067 read(4, "1110 124 106 76 0 97 0\n", 4095) = 23 > 0.000051 close(4) = 0 > 0.000056 stat("/proc/2515", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0 > 0.000079 open("/proc/2515/stat", O_RDONLY) = 4 > 0.000056 read(4, "2515 (top) R 2514 2514 2436 34817 2514 4202496 > 206 0 0 0 0 0 0 0 20 0 1 0 64452 23875584 698 18446744073709551615 > 4194304 4257604 140736479316592 140736479312856 140491962546544 0 0 0 > 2147221247 0 0 0 17 4 0 0 0 0 0 6356400 6361288 22503424 > 140736479321472 140736479321476 140736479321476 140736479322091 0\n", > 4095) = 307 > 0.000125 close(4) = 0 > 0.000063 open("/proc/2515/statm", O_RDONLY) = 4 > 0.000067 read(4, "5829 698 582 16 0 246 0\n", 4095) = 24 > 0.000052 close(4) = 0 > 0.000055 getdents(3, /* 0 entries */, 32768) = 0 > 0.000056 close(3) = 0 > 0.000055 nanosleep({0, 150000000}, NULL) = ? > ERESTART_RESTARTBLOCK (To be restarted) > 10.943440 --- SIGINT (Interrupt) @ 0 (0) --- > > > > Please consider this to be a bug report, hosts are running 4.0.5, qemu > is a tagged 2.3.0 and the guest is debian jessie 3.16. Unfortunately I > do not have much time to bisect this one or go a bit more deeply right > now, hopefully it would be possible on a weekend with enough spare > time. Thanks! > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK