Re: [PATCH v2 00/10] qemu: add option to process offloaded legacy blockjob event ealier
On Fri, Nov 13, 2020 at 09:53:28 +0300, Nikolay Shirokovskiy wrote:
This is successor to [1] but I changed the subject as in the review
the patch
'qemu: sync backing chain update in virDomainGetBlockJobInfo' was not
considered good one from design POV. However I think the basic patch is helpful
to address similar issues. Look at [*] for example, there it allows to sync
backing chains during query block stats.
In discussion of [1] I stated that first patch will also allow to get rid of
stale block job events on reconnection to qemu. But this will require
additional work actually so with this patch series stale events are still
present. And in the discussion it was also mentioned by Peter that stale events
are not harmful for legacy blockjobs code. I also removed previous attempts to
eliminate some of stale events.
I still keep patch for virDomainGetBlockJobInfo. May be in comparsion to [*]
the approach the patch takes will look not so bad :)
[1] First version of the patch series
https://www.redhat.com/archives/libvir-list/2020-October/msg01133.html
I had a look at this series and it's just doing too much just to "fix"
apps which insist on polling especially with pre-blockdev qemu. I simply
it's not worth adding the complexity you are proposing.
NACK series.
Instead I propose we add a workaround which will report fake unfinished
job:
https://www.redhat.com/archives/libvir-list/2020-December/msg00352.html
The scope of this is way more limited and it doesn't actually try to
modify the job code handovers which is very dangerous.
I had a look at this series and it's just doing too much just to "fix"
apps which insist on polling especially with pre-blockdev qemu.
Additionally it adds documentation stating that apps should not poll
virDomainGetBlockJobInfo.