Re: [Qemu-devel] QEMU Summit 2017: minutes

[John Snow]

On 11/28/2017 04:36 AM, Cornelia Huck wrote:
> On Tue, 28 Nov 2017 09:33:52 +0100
> Thomas Huth <address@hidden> wrote:
> 
>> On 27.11.2017 23:03, John Snow wrote:
>>>
>>> On 11/23/2017 11:31 AM, Peter Maydell wrote:  
>> [...]
>>>> Continuous Integration:
>>>>  * Christian Borntraeger: qemu-iotests have broken a lot, they should be
>>>>    run before patches are merged  
>>>
>>> This, rather unfortunately, is a huge testing burden. I try to make sure
>>> I do it for everything I submit, but for the volume of block patches it
>>> really does rely CI. The more we add (to our pitifully sparse iotesting,
>>> I might add) the longer it takes. Ensuring per-patch testing begins to
>>> take prohibitively long.
>>>
>>> Perhaps per-pull or per-merge becomes more feasible. Maybe if we do
>>> implement a block-next amalgam we'd be able to batch our testing on a
>>> weekly basis.  
>>
>> I think you block-layer folks should do at least run the qemu-iotests
>> before sending a pull request to Peter. The iotests should really not be
>> broken in upstream master.
> 
> This is unlikely to cover the iotest failures on s390 (due to usage of
> ccw, strange backing devices, etc.), though. We have basically two
> options here:
> - Continue to rely on the IBM folks finding those problems (which will
>   likely be post-merge, but better than nothing.)
> - Have patchew (which has a bot on s390) execute the iotests - which is
>   time-consuming.
> 

Does patchew test pull requests? Perhaps Peter could wait for an ACK
from patchew before committing. Peter and patchew could check PRs in
tandem and perhaps he can commit fully only when patchew ACKs.

for PRs specifically, perhaps patchew can indeed send an affirmative ACK
to the list indicating success.

>>
>>>>  * Peter Maydell: If it isn't tested by "make check" then it isn't tested:
>>>>    so if something is regularly regressing then it needs to be added to
>>>>    "make check".  
>>>
>>> Is this tenable long term? We can't conceivably state that we will never
>>> test things that aren't in "make check" -- we ought to have different
>>> tiers, at least. The full testing suite should run for RC tags at least,
>>> but it's not feasible (I think?) to run the entire battery of tests on
>>> every commit... but that shouldn't stop us from running them /sometimes/... 
>>>  
>>
>> We've already got "make check SPEED=slow" for running tests that take a
>> lot of time. So maybe you could do that in the iotests as well, so that
>> the normal, quick tests can be run during "make check" and the full
>> iotest suite is only run during "make check SPEED=slow" ?
> 
> +1 to that. Having a subset covered by default is better than nothing
> at all.
> 

Sure, I was just taking issue with Peter's phrasing of 'If it isn't
tested by "make check" then it isn't tested' -- this sounds like policy
we should change and indeed formalize fast and slow paths.

Of course, this is the block maintainers' job more than anyone else's,
hence some other musings above and in my initial reply.