Re: [libvirt PATCH 0/6] cleanup and fixes of the mapped-ram feature
On 3/21/25 04:21, Martin Kletzander wrote:
On Fri, Mar 21, 2025 at 08:29:30AM +0000, Daniel P. Berrangé via
Devel wrote:
> On Thu, Mar 20, 2025 at 09:36:15PM -0600, Jim Fehlig via Devel wrote:
>> On 3/20/25 17:07, Pavel Hrdina via Devel wrote:
>> > Pavel Hrdina (6):
>> > tools: remove --parallel from virsh restore command
>> > tools: remote --parallel from virsh save command
>> > qemu: remove VIR_DOMAIN_SAVE_PARALLEL flag
>>
>> Heh, I'm having one of those "why did I not realize that" moments
:-).
>
> IIRC, original we were using --parallel to decide whether to enable
> the new format, so --parallel with channels == 1 /was/ different
> from not setting --parallel at all.
>
Well, restore should figure out the format and save still has
--image-format without which parallel save will fail (unless you have it
set as default in a config). So I think this series is fine, at least
it fixes the unit tests.
Reviewed-by: Martin Kletzander <mkletzan(a)redhat.com>
But there's more to it than meets the eye.
There is also a check that the number of parallel channels is not lower
than 1, for saving. Restoring happily takes parallel.channels=0 and (at
least for non-sparse images) fails weirdly with:
error: Failed to restore domain from test.img
error: Failed to open file 'test.img': No such file or directory
and the daemon reports:
2025-03-21 10:00:08.490+0000: 4076349: error : virFileIsSharedFSType:3598 :
Invalid relative path 'test.img': Invalid argument
2025-03-21 10:00:08.490+0000: 4076349: error : virQEMUFileOpenAs:10448 : Failed
to open file 'test.img': No such file or directory
even though the file exists. And it works without --parallel-channels,
this only happens with --parallel-channels 0.
Opps, I didn't test that. I did verify save with '--parallel-channels 0' is
handled properly.
Last, but not least, our CI is broken with the patches here. And that
is because now one cannot do save-image-edit, with both the new and the
old format with:
error: failed to write header to domain save file '/home/nert/test.img': Bad
file descriptor
I didn't check save-image-edit :-/.
And that's about what I've found out. I'll spend some time on this,
trying to fix it up, but if anyone has a fix ready, then even better.
I've committed to a task that involves others today, so wont be able to look at
these issues until later.
What I'd like to know is whether we can
Did you have more to say? :-)
Regards,
Jim