Re: Misuse of TimestampDifference() in the autoprewarm feature of pg_prewarm

On 2020-11-11 06:59, Tom Lane wrote:
> Alexey Kondratov <a(dot)kondratov(at)postgrespro(dot)ru> writes:
>> After looking on the autoprewarm code more closely I have realised
>> that
>> this 'double dump' issues was not an issues at all. I have just
>> misplaced a debug elog(), so its second output in the log was only
>> indicating that we calculated delay_in_ms one more time.
>
> Ah --- that explains why I couldn't see a problem.
>
> I've pushed 0001+0002 plus some followup work to fix other places
> that could usefully use TimestampDifferenceMilliseconds(). I have
> not done anything with 0003 (the TAP test for pg_prewarm), and will
> leave that to the judgment of somebody who's worked with pg_prewarm
> before. To me it looks like it's not really testing things very
> carefully at all; on the other hand, we have exactly zero test
> coverage of that module today, so maybe something is better than
> nothing.
>

Great, thank you for generalisation of the issue and working on it.

Regards
--
Alexey Kondratov

Postgres Professional https://www.postgrespro.com
Russian Postgres Company