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

On 2020/04/03 12:30, Tom Lane wrote:
> Fujii Masao <masao(dot)fujii(at)oss(dot)nttdata(dot)com> writes:
>> On 2020/04/03 11:58, Michael Paquier wrote:
>>> prion did not like that:
>>> https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=prion&dt=2020-04-03%2002%3A33%3A13
>
> dory failed as well. The problem is that in text mode, a Buffers line
> won't appear at all if there were zero buffer accesses. I don't think
> we really want to change that,

Yes.

> so probably the thing to do is adapt
> the filter functions in explain.sql so that they suppress Buffers lines
> altogether in text output. Kind of annoying, but ...

I'm thinking to suppress only Buffers line just after Planning Time line,
by applying something like the following changes to explain_filter().
Thought?

declare
ln text;
+ ignore_output boolean;
begin
for ln in execute $1
loop
+ IF ignore_output THEN
+ ignore_output := false;
+ CONTINUE WHEN (ln ~~ ' Buffers: %');
+ END IF;
+ ignore_output := ln ~~ 'Planning Time: %';
-- Replace any numeric word with just 'N'
ln := regexp_replace(ln, '\m\d+\M', 'N', 'g');
-- In sort output, the above won't match units-suffixed numbers

Regards,

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