Re: BackgroundPsql swallowing errors on windows

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.

cheers

andrew

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