Bug 740899
Summary: | [qemu-kvm][scalability] qemu could not open disk error at 256 devices | ||
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Product: | Red Hat Enterprise Linux 6 | Reporter: | Dave Allan <dallan> |
Component: | libvirt | Assignee: | Eric Blake <eblake> |
Status: | CLOSED ERRATA | QA Contact: | Virtualization Bugs <virt-bugs> |
Severity: | medium | Docs Contact: | |
Priority: | high | ||
Version: | 6.1 | CC: | abaron, acathrow, ajia, cpelland, danken, ddumas, dnaori, dyuan, eblake, iheim, juzhang, kwolf, leiwang, mburns, mgoldboi, michen, mkenneth, perfbz, rwu, shuang, tburke, veillard, virt-maint, weizhan, xfu, yeylon, ykaul |
Target Milestone: | rc | ||
Target Release: | --- | ||
Hardware: | x86_64 | ||
OS: | Linux | ||
Whiteboard: | |||
Fixed In Version: | libvirt-0.9.4-15.el6 | Doc Type: | Bug Fix |
Doc Text: | Story Points: | --- | |
Clone Of: | 739489 | Environment: | |
Last Closed: | 2011-12-06 11:34:23 UTC | Type: | --- |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: | |||
Bug Depends On: | |||
Bug Blocks: | 611326, 747120 |
Comment 12
Eric Blake
2011-10-04 15:36:33 UTC
Upstream patch awaiting review: https://www.redhat.com/archives/libvir-list/2011-October/msg00075.html can reproduce on qemu-kvm-0.12.1.2-2.195.el6.x86_64 kernel-2.6.32-206.el6.x86_64 libvirt-0.9.4-12.el6.x86_64 test on machine intel-e7420-128-1 change the /proc/sys/fs/aio-max-nr to 65535 with attach 513 disks like <disk type='block' device='disk'> <driver name='qemu' type='raw' cache='none' io='native'/> <source dev='/dev/vg0/guest1-u'/> <target dev='vdu' bus='virtio'/> </disk> when start 21th guests, it reports error error: Failed to start domain guest21 error: internal error Process exited while reading console log output: char device redirected to /dev/pts/22 qemu-kvm: -drive file=/dev/vg0/guest21-l,if=none,id=drive-virtio-disk11,format=raw,cache=none,aio=native: could not open disk image /dev/vg0/guest21-l: Invalid argument on libvirt-0.9.4-16.el6.x86_64, report the same error, qemu-kvm bug is still in New status, so add depends on bug 739489 Remember that the libvirt fix is to set a sysfs setting at boot. The only way to verify the behavior of this fix is to install the desired libvirt (whether to prove the bug exists in older libvirt or to prove it is fixed with newer libvirt), then reboot the system, then 'cat /proc/sys/fs/aio-max-nr', then run the test with more than 256 disks. The reboot between each change of libvirt is essential to prove that /etc/sysctl.d is being sourced correctly at bootup as part of the fix. (In reply to comment #23) > Remember that the libvirt fix is to set a sysfs setting at boot. The only way > to verify the behavior of this fix is to install the desired libvirt (whether > to prove the bug exists in older libvirt or to prove it is fixed with newer > libvirt), then reboot the system, then 'cat /proc/sys/fs/aio-max-nr', then run > the test with more than 256 disks. The reboot between each change of libvirt > is essential to prove that /etc/sysctl.d is being sourced correctly at bootup > as part of the fix. Thanks for Eric's reminding. I retest with the following steps on libvirt-0.9.4-16 1. install libvirt-0.9.4.12 and reboot host 2. check the aio limit #cat /proc/sys/fs/aio-max-nr 65536 3. Start 22 guests with 24 disks on each guest and aio=native On the 22th guest start, it will report error like error: Failed to start domain guest22 error: internal error Process exited while reading console log output: char device redirected to /dev/pts/23 qemu-kvm: -drive file=/var/lib/libvirt/images/guest22-h.img,if=none,id=drive-virtio-disk7,format=raw,cache=none,aio=native: could not open disk image /var/lib/libvirt/images/guest22-h.img: Inappropriate ioctl for device 4. update to libvirt-0.9.4-16 and reboot host again 5. check the aio limit again #cat /proc/sys/fs/aio-max-nr 1048576 6. Start 22 guests with 24 disks on each guest and aio=native All the guest can started successfully So verify pass qemu-kvm-0.12.1.2-2.195.el6.x86_64 kernel-2.6.32-206.el6.x86_64 Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHBA-2011-1513.html |