Re: [libvirt-users] Libvirtd freezes

Stefano Ricci
Sat, 29 Apr 2017 02:38:33 -0000

2017-04-28 14:33 GMT+02:00 Michal Privoznik
<mprivozn@redhat.com>:
> On 04/27/2017 04:31 PM, Stefano Ricci wrote:
>> Here is the backtrace of the libvirt process just started
>
> [Just a side note, you shouldn't top post on technical lists. Gmail
> sucks at this.]
>
>>
>> https://pastebin.com/R66myzFp
>
> Looks like libvirtd is trying to spawn /usr/bin/qemu-system-x86_64 but
> it takes ages to init. In the debug logs you might see the actual
> command line that libvirt tries to execute. You can try running it by
> hand and see if it takes about the same time. If so, then it's a qemu
bug.
>
> http://wiki.libvirt.org/page/DebugLogs
>
> Michal

The line that comes from the libvirt log is as follows:
LC_ALL=C PATH=/bin:/usr/bin:/sbin:/usr/sbin HOME=/ USER=root
/usr/bin/qemu-system-x86_64 -S -no-user-config -nodefaults -nographic
-M none -qmp unix:/var/lib/libvirt/qemu/capabilities.monitor.sock,server,nowait
-pidfile /var/lib/libvirt/qemu/capabilities.pidfile -daemonize
Before I run the command manually I added the -D parameter to write
the qemu process stderr in a log file.
Once the command is executed, the log file is blank then error-free
and the process seems to respond correctly.
I have connected with the following command: nc -U
/var/lib/libvirt/qemu/capabilities.monitor.sock
and this is an extract of qemu output to my requests:
{"QMP": {"version": {"qemu": {"micro":
1, "minor": 8, "major": 2},
"package": ""}, "capabilities": []}}
{ "execute": "qmp_capabilities" }
{"return": {}}
{ "execute": "query-commands" }
{"return": [{"name": "xen-set-global-dirty-log"},
{"name":
"xen-save-devices-state"}, {"name":
"xen-load-devices-state"},
{"name": "x-colo-lost-heartbeat"}, {"name":
"x-blockdev-remove-medium"}, {"name":
"x-blockdev-insert-medium"},
{"name": "x-blockdev-del"}, {"name":
"x-blockdev-change"}, {"name":
"transaction"}, {"name": "trace-event-set-state"},
{"name":
"trace-event-get-state"}, {"name":
"system_wakeup"}, {"name":
"system_reset"}, {"name": "system_powerdown"},
{"name": "stop"},
{"name": "set_password"}, {"name":
"set_link"}, {"name": "send-key"},
{"name": "screendump"}, {"name":
"rtc-reset-reinjection"}, {"name":
"ringbuf-write"}, {"name": "ringbuf-read"},
{"name": "remove-fd"},
{"name": "quit"}, {"name":
"query-vnc-servers"}, {"name":
"query-vnc"}, {"name": "query-version"},
{"name": "query-uuid"},
{"name": "query-tpm-types"}, {"name":
"query-tpm-models"}, {"name":
"query-tpm"}, {"name": "query-target"},
{"name": "query-status"},
{"name": "query-spice"}, {"name":
"query-rx-filter"}, {"name":
"query-rocker-ports"}, {"name":
"query-rocker-of-dpa-groups"},
{"name": "query-rocker-of-dpa-flows"}, {"name":
"query-rocker"},
{"name": "query-pci"}, {"name":
"query-named-block-nodes"}, {"name":
"query-name"}, {"name":
"query-migrate-parameters"}, {"name":
"query-migrate-capabilities"}, {"name":
"query-migrate-cache-size"},
{"name": "query-migrate"}, {"name":
"query-mice"}, {"name":
"query-memory-devices"}, {"name": "query-memdev"},
{"name":
"query-machines"}, {"name": "query-kvm"},
{"name": "query-iothreads"},
{"name": "query-hotpluggable-cpus"}, {"name":
"query-fdsets"},
{"name": "query-events"}, {"name":
"query-dump-guest-memory-capability"}, {"name":
"query-dump"},
{"name": "query-cpus"}, {"name":
"query-cpu-definitions"}, {"name":
"query-commands"}, {"name":
"query-command-line-options"}, {"name":
"query-chardev-backends"}, {"name":
"query-chardev"}, {"name":
"query-blockstats"}, {"name": "query-block-jobs"},
{"name":
"query-block"}, {"name": "query-balloon"},
{"name":
"query-acpi-ospm-status"}, {"name": "qom-set"},
{"name":
"qom-list-types"}, {"name": "qom-list"},
{"name": "qom-get"}, {"name":
"qmp_capabilities"}, {"name": "pmemsave"},
{"name": "object-del"},
{"name": "object-add"}, {"name":
"netdev_del"} .......
So it would not look like a qemu bug.

Stefano