[ovs-dev] [PATCH ovn v2 6/6] ovn-northd-ddlog: New implementation of ovn-northd based on ddlog.

[Dumitru Ceara]

On 11/6/20 4:18 AM, Ben Pfaff wrote:
> On Thu, Nov 05, 2020 at 08:26:34PM +0100, Dumitru Ceara wrote:
>> On 11/5/20 6:10 AM, Ben Pfaff wrote:
>>> From: Leonid Ryzhyk <lryzhyk at vmware.com>
>>>
>>> This implementation is incremental, meaning that it only recalculates
>>> what is needed for the southbound database when northbound changes
>>> occur.  It is expected to scale better than the C implementation,
>>> for large deployments.  (This may take testing and tuning to be
>>> effective.)
>>>
>>> There are three tests that I'm having mysterious trouble getting
>>> to work with DDlog.  For now, I've marked the testsuite to skip
>>> them unless RUN_ANYWAY=yes is set in the environment.
>>>
>>> Signed-off-by: Leonid Ryzhyk <lryzhyk at vmware.com>
>>> Co-authored-by: Justin Pettit <jpettit at ovn.org>
>>> Signed-off-by: Justin Pettit <jpettit at ovn.org>
>>> Co-authored-by: Ben Pfaff <blp at ovn.org>
>>> Signed-off-by: Ben Pfaff <blp at ovn.org>
>>
>> Hi Ben,
>>
>> As discussed during the community meeting earlier, with OVS master, OVN
>> master + this series applied I see some test failures:
>> # make check TESTSUITEFLAGS="65 67 73 81 91 101 145 175 189 207 270 275
>> 281 292 326 348 423"
>>
>> I didn't investigate why these failed but I attached testsuite.log.
> 
> For most of these, the problem is probably that there is a missing
> "ovn-nbctl sync" call to make sure that ovn-northd[-ddlog] is caught
> up.  I'll put that, and some other improvements that should make
> remaining problems (if any) either to diagnose, in v3.
> 
> Some of these are from ovn-northd, not ovn-northd-ddlog, and so I don't
> think it's likely that my patch series causes them, since it doesn't
> really touch ovn-northd.  The OVN testsuite has a regrettable number of
> race conditions in it.
> 

I agree, there are probably races in the testsuite but I think there's
also a bug with "ovn-nbctl --wait=hv sync".

For example, adding a "sleep 1" here:
https://github.com/ovn-org/ovn/blob/c108f23e1c10910031f9409b79001d001aae0c8f/tests/ovn.at#L21478

makes this test pass on my machine with both ovn-northd and
ovn-northd-ddlog.

In any case, it's most likely not related to your patch series indeed.
I'll debug some more.

Regards,
Dumitru