Re: BackgroundPsql swallowing errors on windows

On 2026-06-03 We 5:23 PM, Andrew Dunstan wrote:
>
> On 2026-06-02 Tu 3:03 PM, Andrew Dunstan wrote:
>>
>> On 2026-02-18 We 2:41 PM, Andrew Dunstan wrote:
>>>
>>> On 2026-02-17 Tu 4:56 PM, Andres Freund wrote:
>>>> Hi,
>>>>
>>>> On 2026-02-17 16:31:02 -0500, Andrew Dunstan wrote:
>>>>> On 2026-02-16 Mo 7:17 PM, Andres Freund wrote:
>>>>>> I briefly tried this out. The overall resource usage of the test
>>>>>> is noticeably
>>>>>> reduced - and that's on linux with fast fork, so it should be
>>>>>> considerably
>>>>>> better on windows.  However, the tests take a lot longer than
>>>>>> before, I think
>>>>>> mostly due to polling for results rather than waiting for them to
>>>>>> be ready
>>>>>> using PQsocketPoll() or such.
>>>>>>
>>>>>> E.g. bloom/001_wal takes about 15s on HEAD for me, but 138s with
>>>>>> the patch. I
>>>>>> think that's just due to the various usleep(100_000);
>>>>>>
>>>>>>
>>>>>> FWIW, oauth_validator/001_server fails with the patch at the moment.
>>>>>>
>>>>> Try this version. On my machine it's now a few percent faster. I
>>>>> fixed the
>>>>> polling. I also added pipeline support for large sets of commands, to
>>>>> minimize roundtrips.
>>>> Nice!  Will try it out.
>>>>
>>>>
>>>> Have you tried it on windows already? That's where we pay by far
>>>> the biggest
>>>> price due to all the unnecessary process creations...
>>>>
>>>> It looks like strawberry perl has FFI::Platypus, but not FFI::C. 
>>>> There is
>>>> perl/vendor/lib/FFI/Platypus/Lang/C.pm, but that just seems like it's
>>>> documentation.  There is however FFI::Platypus::Record, which maybe
>>>> could
>>>> suffice?
>>>>
>>>> Do we actually need FFI::C, or can we work around not having it?
>>>> Looks like
>>>> it's just used for notify related stuff.
>>>>
>>>> It looks like mingw doesn't have packages for FFI::Platypus, but it'll
>>>> probably be a lot easier to build that than when using msvc.
>>>>
>>>>
>>>
>>> I replaced the use of FFI::C with FFI::Platypus::Record. That comes
>>> for free with FFI::Platypus, so there would be no extra dependency.
>>> It means a little extra housekeeping so we don't lose track of the
>>> pointer for later use with PQfreemem, but it's not too bad.
>>>
>>> I have tried it out with Windows, seemed to work OK although the
>>> xid_wraparound tests 2 and 3 timed out.
>>>
>>> Latest is attached.
>>>
>>>
>>>
>>
>> Here is v12. I removed the XS variant in this version, which makes
>> things simpler. We can restore it if necessary.
>>
>> Patch 1 adds the new framework
>>
>> Patch 2 adapts Cluster.pm to it, as well as handling some instability
>> at global destruction time that was exacerbated by using FFI::Platypus.
>>
>> Patch 3 makes improvements in the individual TAP tests using the
>> framework, including removing every one of the calls to
>> background_psql().
>>
>>
>> I'm going to add this to the CF and will start testing (again) on
>> Windows.
>>
>>
>>
>
> v13 attached now passes all tests on my Windows machine.
>
>
>

rebased, including porting a new use of background_psql.

cheers

andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com