[libvirt-users] Libvirtd freezes

[Stefano Ricci]

2017-04-29 7:24 GMT+02:00 Michal Privoznik <mprivozn at redhat.com>:
> On 04/29/2017 04:38 AM, Stefano Ricci wrote:
>> 2017-04-28 14:33 GMT+02:00 Michal Privoznik <mprivozn at 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.
>
> Well, this does not prove that qemu replies to all commands issued by
> libvirt. For that we would need debug logs as referred to above.
>
> BTW: The stack trace looks a bit old (the line number do not match with
> the current git HEAD) - what's the release you're running and does the
> problem occur with the current git HEAD too?
>
> Michal

The version used for backtrace is 3.2.0, now I have also tried the
current downloaded with git but the problem is always present.
This is the current version log file, set as shown on the DebugLogs page:

https://drive.google.com/open?id=0By9lwQyveHENdEt4aEtZcUV3ZEU

Stefano