Re: pgsql: Include information on buffer usage during planning phase, in EX

On 2020/04/03 11:58, Michael Paquier wrote:
> Hi Fujii-san,
>
> On Fri, Apr 03, 2020 at 02:28:27AM +0000, Fujii Masao wrote:
>> Include information on buffer usage during planning phase, in EXPLAIN output.
>>
>> When BUFFERS option is enabled, EXPLAIN command includes the information
>> on buffer usage during each plan node, in its output. In addition to that,
>> this commit makes EXPLAIN command include also the information on
>> buffer usage during planning phase, in its output. This feature makes it
>> easier to discern the cases where lots of buffer access happen during
>> planning.
>
> prion did not like that:
> https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=prion&dt=2020-04-03%2002%3A33%3A13
>
> Here is the diff from test explain:
> @@ -73,8 +73,9 @@
> Seq Scan on int8_tbl i8 (cost=N.N..N.N rows=N width=N) (actual time=N.N..N.N rows=N loops=N)
> Buffers: shared [read]
> Planning Time: N.N ms
> + Buffers: shared [read]
> Execution Time: N.N ms
> -(4 rows)
> +(5 rows)
>
> Note that this animal uses -DRELCACHE_FORCE_RELEASE and
> -DCATCACHE_FORCE_RELEASE.

Thanks for reporting that!

Since we're now developing very heavily because of the last CF,
it's not good to keep the buildfarm red for a long time. So I just
reverted the commit. Then I will consider how to address the issue.

Regards,

--
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION