Public bug reported: Binary package hint: qemu-kvm
Steps to reproduce: - Use qemu-img convert to convert an image. e.g. a large (40GB) raw file to a compressed qcow2 image - Watch the load rise - kernel messages will be like "INFO: task blocked for more than 120 seconds". (Also see below) In some cases this will bring down the server. When running libvirt too, all virtual servers will timeout/crash. Using ionice to renice qemu-img convert does not really prevent the issue. kvm D 0000000000000000 0 9632 1 0x00000000 ffff8801a4269ca8 0000000000000086 0000000000015bc0 0000000000015bc0 ffff8802004fdf38 ffff8801a4269fd8 0000000000015bc0 ffff8802004fdb80 0000000000015bc0 ffff8801a4269fd8 0000000000015bc0 ffff8802004fdf38 Call Trace: [<ffffffff815596b7>] __mutex_lock_slowpath+0x107/0x190 [<ffffffff815590b3>] mutex_lock+0x23/0x50 [<ffffffff810f5899>] generic_file_aio_write+0x59/0xe0 [<ffffffff811d7879>] ext4_file_write+0x39/0xb0 [<ffffffff81143a8a>] do_sync_write+0xfa/0x140 [<ffffffff81084380>] ? autoremove_wake_function+0x0/0x40 [<ffffffff81252316>] ? security_file_permission+0x16/0x20 [<ffffffff81143d88>] vfs_write+0xb8/0x1a0 [<ffffffff81144722>] sys_pwrite64+0x82/0xa0 [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b kdmflush D 0000000000000002 0 396 2 0x00000000 ffff88022eeb3d10 0000000000000046 0000000000015bc0 0000000000015bc0 ffff88022f489a98 ffff88022eeb3fd8 0000000000015bc0 ffff88022f4896e0 0000000000015bc0 ffff88022eeb3fd8 0000000000015bc0 ffff88022f489a98 ProblemType: Bug DistroRelease: Ubuntu 10.04 Package: qemu-kvm 0.12.3+noroms-0ubuntu9.3 ProcVersionSignature: Ubuntu 2.6.32-28.55-server 2.6.32.27+drm33.12 Uname: Linux 2.6.32-28-server x86_64 Architecture: amd64 Date: Thu Feb 3 12:34:13 2011 KvmCmdLine: UID PID PPID C SZ RSS PSR STIME TTY TIME CMD root 1809 1 0 188145 517408 3 Jan31 ? 00:21:36 /usr/bin/kvm -S -M pc-0.11 -enable-kvm -m 512 -smp 1 -name jessica -uuid 76a39821-a89d-1ac7-65c2-40464dc21043 -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/jessica.monitor,server,nowait -monitor chardev:monitor -boot c -drive if=ide,media=cdrom,index=2,format=raw -drive file=/var/lib/libvirt/images/jessica.img,if=virtio,index=0,boot=on,format=qcow2 -net nic,macaddr=54:52:00:5f:d8:2c,vlan=0,model=virtio,name=virtio.0 -net tap,fd=39,vlan=0,name=tap.0 -chardev pty,id=serial0 -serial chardev:serial0 -parallel none -usb -vnc 127.0.0.1:0 -vga cirrus root 1909 1 0 248235 625280 3 Jan31 ? 00:21:14 /usr/bin/kvm -S -M pc-0.11 -enable-kvm -m 768 -smp 1 -name gurney -uuid 7a21a182-8349-b17d-7eff-64f9bb3e7e30 -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/gurney.monitor,server,nowait -monitor chardev:monitor -boot c -drive if=ide,media=cdrom,index=2,format=raw -drive file=/var/lib/libvirt/images/gurney.img,if=virtio,index=0,boot=on,format=qcow2 -net nic,macaddr=54:52:00:52:dc:a0,vlan=0,model=virtio,name=virtio.0 -net tap,fd=41,vlan=0,name=tap.0 -chardev pty,id=serial0 -serial chardev:serial0 -parallel none -usb -vnc 127.0.0.1:2 -vga cirrus root 27120 1 0 193095 552120 0 Jan31 ? 00:27:52 /usr/bin/kvm -S -M pc-0.11 -cpu qemu32 -enable-kvm -m 512 -smp 1 -name kolab -uuid 79b2a347-7841-39df-8399-c072b05e7f6f -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/kolab.monitor,server,nowait -monitor chardev:monitor -boot c -drive if=ide,media=cdrom,index=2,format=raw -drive file=/srv/libvirt/leto/kolab.img,if=virtio,index=0,boot=on,format=qcow2 -net nic,macaddr=54:52:00:63:ee:4f,vlan=0,model=virtio,name=virtio.0 -net tap,fd=40,vlan=0,name=tap.0 -chardev pty,id=serial0 -serial chardev:serial0 -parallel none -usb -vnc 127.0.0.1:1 -vga cirrus ProcCmdLine: BOOT_IMAGE=/vmlinuz-2.6.32-28-server root=/dev/mapper/vg0-root ro quiet splash delayacct ProcEnviron: PATH=(custom, user) LANG=C SHELL=/bin/bash SourcePackage: qemu-kvm dmi.bios.date: 02/23/2010 dmi.bios.vendor: Intel Corp. dmi.bios.version: CBQ4510H.86A.0119.2010.0223.1522 dmi.board.asset.tag: To be filled by O.E.M. dmi.board.name: DQ45CB dmi.board.vendor: Intel Corporation dmi.board.version: AAE30148-301 dmi.chassis.type: 3 dmi.modalias: dmi:bvnIntelCorp.:bvrCBQ4510H.86A.0119.2010.0223.1522:bd02/23/2010:svn:pn:pvr:rvnIntelCorporation:rnDQ45CB:rvrAAE30148-301:cvn:ct3:cvr: ** Affects: qemu-kvm (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug lucid -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to qemu-kvm in ubuntu. https://bugs.launchpad.net/bugs/712392 Title: qemu-img convert blocks other tasks -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs