From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48150) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WiZ4U-0004T0-PG for qemu-devel@nongnu.org; Thu, 08 May 2014 20:54:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WiZ4M-0007Wt-HX for qemu-devel@nongnu.org; Thu, 08 May 2014 20:53:54 -0400 Received: from mail1.windriver.com ([147.11.146.13]:35116) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WiZ4M-0007Uy-9y for qemu-devel@nongnu.org; Thu, 08 May 2014 20:53:46 -0400 Message-ID: <536C2712.3030803@windriver.com> Date: Thu, 8 May 2014 18:53:38 -0600 From: Chris Friesen MIME-Version: 1.0 References: <53693FA4.3000306@windriver.com> <5369D504.2070101@redhat.com> <536AB2EE.6010504@windriver.com> <20140508130231.GA24978@grmbl.mre> <536B8332.9070705@redhat.com> <20140508133052.GA25602@grmbl.mre> <536B884D.6080504@redhat.com> <20140508134738.GB25602@grmbl.mre> <536BA579.10604@windriver.com> In-Reply-To: <536BA579.10604@windriver.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] virtio-serial-pci very expensive during live migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amit Shah , Paolo Bonzini Cc: qemu-devel@nongnu.org, armbru@redhat.com On 05/08/2014 09:40 AM, Chris Friesen wrote: > On 05/08/2014 07:47 AM, Amit Shah wrote: > >> Chris, I just tried a simple test this way: >> >> ./x86_64-softmmu/qemu-system-x86_64 -device virtio-serial-pci -device >> virtserialport -S -monitor stdio -nographic >> >> and it didn't crash for me. This was with qemu.git. Perhaps you can >> try in a similar way. > > I just tried it with the "stable-1.4" branch from upstream with my first > patch added on. > Anyway, it seems to boot up okay, which is better than what I was > getting before. Turns out I spoke too soon. With the patch applied, it boots, but if I try to do a live migration both the source and destination crash. This happens for both the master branch as well as the stable-1.4 branch. If I back out the patch, it works fine. If I leave the patch in and disable kvm acceleration it works fine. I'm running the source as /tmp/qemu-system-x86_64-upstream -machine accel=kvm -m 1000 test-cgcs-guest.img -device virtio-serial -chardev socket,path=/tmp/foo,server,nowait,id=foo -device virtserialport,chardev=foo,name=myfoo -monitor stdio and the dest as /tmp/qemu-system-x86_64-upstream -machine accel=kvm -m 1000 test-cgcs-guest.img -device virtio-serial -chardev socket,path=/tmp/foo,server,nowait,id=foo -device virtserialport,chardev=foo,name=myfoo -monitor stdio -incoming tcp:0:4444 and I'm triggering the migration with migrate -d tcp:localhost:4444 On the dest side monitor I get: (qemu) qemu: warning: error while loading state section id 3 load of migration failed I managed to get gdb working, but it's not very helpful. With gdb attached to the destination process I just get: [Thread 0x7f760f6dc700 (LWP 15328) exited] [Inferior 1 (process 15326) exited normally]