Re: How to tame CI?

[Thomas Huth <thuth@redhat.com>]

On 26/07/2023 15.00, Peter Maydell wrote:
> On Wed, 26 Jul 2023 at 13:06, Juan Quintela <quintela@redhat.com> wrote:
>> To make things easier, this is the part that show how it breaks (this is
>> the gcov test):
>>
>> 357/423 qemu:block / io-qcow2-copy-before-write                            ERROR           6.38s   exit status 1
>>>>> PYTHON=/builds/juan.quintela/qemu/build/pyvenv/bin/python3 MALLOC_PERTURB_=44 /builds/juan.quintela/qemu/build/pyvenv/bin/python3 /builds/juan.quintela/qemu/build/../tests/qemu-iotests/check -tap -qcow2 copy-before-write --source-dir /builds/juan.quintela/qemu/tests/qemu-iotests --build-dir /builds/juan.quintela/qemu/build/tests/qemu-iotests
>> ――――――――――――――――――――――――――――――――――――― ✀  ―――――――――――――――――――――――――――――――――――――
>> stderr:
>> --- /builds/juan.quintela/qemu/tests/qemu-iotests/tests/copy-before-write.out
>> +++ /builds/juan.quintela/qemu/build/scratch/qcow2-file-copy-before-write/copy-before-write.out.bad
>> @@ -1,5 +1,21 @@
>> -....
>> +...F
>> +======================================================================
>> +FAIL: test_timeout_break_snapshot (__main__.TestCbwError)
>> +----------------------------------------------------------------------
>> +Traceback (most recent call last):
>> +  File "/builds/juan.quintela/qemu/tests/qemu-iotests/tests/copy-before-write", line 210, in test_timeout_break_snapshot
>> +    self.assertEqual(log, """\
>> +AssertionError: 'wrot[195 chars]read 1048576/1048576 bytes at offset 0\n1 MiB,[46 chars]c)\n' != 'wrot[195 chars]read failed: Permission denied\n'
>> +  wrote 524288/524288 bytes at offset 0
>> +  512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
>> +  wrote 524288/524288 bytes at offset 524288
>> +  512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
>> ++ read failed: Permission denied
>> +- read 1048576/1048576 bytes at offset 0
>> +- 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
>> +
> 
> This iotest failing is an intermittent that I've seen running
> pullreqs on master. I tend to see it on the s390 host. I
> suspect a race condition somewhere where it fails if the host
> is heavily loaded.

It's obviously a failure in an iotest, so let's CC: the corresponding people 
(done now).

  Thomas