Re: why is pg_upgrade's regression run so slow? - Mailing list pgsql-hackers

From Alexander Lakhin
Subject Re: why is pg_upgrade's regression run so slow?
Date
Msg-id 35fe76b6-845f-bd8b-d2bf-8c824230d28a@gmail.com
Whole thread Raw
In response to Re: why is pg_upgrade's regression run so slow?  (Andrew Dunstan <andrew@dunslane.net>)
Responses Re: why is pg_upgrade's regression run so slow?
List pgsql-hackers
Hello Andrew,

28.07.2024 22:43, Andrew Dunstan wrote:
>
> Maybe, IDK. Meanwhile, I disabled "debug_parallel_query = regress" on HEAD for fairywren and drongo -  fairwren has 
> just gone green, and I expect drongo will when it reports in a few hours.
>
> I'm at a loss for an explanation.
>

I'm observing the same here (using a Windows 10 VM).

With no TEMP_CONFIG set, `meson test` gives me these numbers:
test:         postgresql:pg_upgrade / pg_upgrade/002_pg_upgrade
duration:     72.34s

test:         postgresql:regress / regress/regress
duration:     41.98s

But with debug_parallel_query=regress in TEMP_CONFIG, I see:
test:         postgresql:regress / regress/regress
duration:     50.08s

test:         postgresql:pg_upgrade / pg_upgrade/002_pg_upgrade
duration:     398.45s

With log_min_messages=DEBUG2 added to TEMP_CONFIG, I can see how many
parallel workers were started during the test:
...\postgresql\build>grep "starting background worker process" -r testrun/pg_upgrade | wc -l
17532

And another interesting fact is that TEMP_CONFIG is apparently ignored by
`meson test regress/regress`. For example, with temp.config containing
invalid settings, `meson test pg_upgrade/002_pg_upgrade` fails, but
`meson test regress/regress` passes just fine.

Best regards,
Alexander



pgsql-hackers by date:

Previous
From: "a.kozhemyakin"
Date:
Subject: Re: Visibility bug with prepared transaction with subtransactions on standby
Next
From: Amit Kapila
Date:
Subject: Re: Conflict detection and logging in logical replication