Re: [PATCH 0/2] tests/migration: Fix migration-test slowdown

[Juan Quintela]

Thomas Huth <thuth@redhat.com> wrote:
> On 12/04/2023 16.19, Juan Quintela wrote:
>> Since commit:
>> commit 1bfc8dde505f1e6a92697c52aa9b09e81b54c78f
>> Author: Dr. David Alan Gilbert <dgilbert@redhat.com>
>> Date:   Mon Mar 6 15:26:12 2023 +0000
>>      tests/migration: Tweek auto converge limits check
>>      Thomas found an autoconverge test failure where the
>>      migration completed before the autoconverge had kicked in.
>>      [...]
>> migration-test has become very slow.
>> On my laptop, before that commit migration-test takes 2min10seconds
>> After that commit, it takes around 11minutes
>> We can't revert it because it fixes a real problem when the host
>> machine is overloaded.  See the comment on test_migrate_auto_converge().
>
> Thanks, your patches decrease the time to run the migration-test from
> 16 minutes down to 5 minutes on my system, that's a great improvement,
> indeed!
>
> Tested-by: Thomas Huth <thuth@redhat.com>
>
> (though 5 minutes are still quite a lot for qtests ... maybe some
> other parts could be moved to only run with g_test_slow() ?)

And once that we are on this topic.  Is there a way to launch several
tests on the same binary on parallel?
i.e. every migration thread uses a maximum of 2 cores, so in a server I
can run several at the same time (I know that migration-test.c tests
need to be modified so they don't interfere, but I have that changes on
my tree), but I don't know of a way to launch them.

Thanks, Juan.

PD, and I don't know why launching a qemu is so slow, the minimal time
that I am able to get for launching the two qemus is around 0.5 seconds.

Later, Juan.