Re: BackgroundPsql swallowing errors on windows

From: Andrew Dunstan <andrew(at)dunslane(dot)net>
To: Andres Freund <andres(at)anarazel(dot)de>
Cc: pgsql-hackers(at)postgresql(dot)org, Noah Misch <noah(at)leadboat(dot)com>
Subject: Re: BackgroundPsql swallowing errors on windows
Date: 2026-06-12 22:39:38
Message-ID: 455b56c8-436d-45fe-b70b-314e11ca65fc@dunslane.net
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers


On 2026-06-10 We 4:23 PM, Andrew Dunstan wrote:
>
> 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.
>
>
>

v15 including a check for FFI::Platypus at setup time, and CI
modifications to allow tests to pass.

cheers

andrew

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

Attachment Content-Type Size
v15-0001-Add-PostgreSQL-Test-Session-for-libpq-based-TAP-.patch text/x-patch 60.5 KB
v15-0002-Use-PostgreSQL-Test-Session-within-the-TAP-test-.patch text/x-patch 6.9 KB
v15-0003-Convert-TAP-tests-to-PostgreSQL-Test-Session.patch text/x-patch 174.2 KB
v15-0004-ci-make-the-TAP-test-jobs-work-with-PostgreSQL-T.patch text/x-patch 5.4 KB
v15-0005-Check-for-FFI-Platypus-when-TAP-tests-are-enable.patch text/x-patch 6.9 KB

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Baji Shaik 2026-06-12 22:50:18 [PATCH] COPY TO FORMAT json: respect column list order
Previous Message Baji Shaik 2026-06-12 22:34:59 Re: uuidv7 improperly accepts dates before 1970-01-01