Subject: Re: track_planning causing performance regression
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: Pavel Stehule <pavel.stehule@gmail.com>, Peter Geoghegan <pg@bowt.ie>,
 Julien Rouhaud <rjuju123@gmail.com>, "Tharakan, Robins" <tharar@amazon.com>,
 pgsql-hackers@postgresql.org
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From: Fujii Masao <masao.fujii@oss.nttdata.com>
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Date: Wed, 21 Apr 2021 23:38:52 +0900
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On 2021/04/19 23:55, Justin Pryzby wrote:
> What does "kind" mean ?  I think it means a "normalized" query or a "query
> structure".
> 
> "a fewer kinds" is wrong, so I think the docs should say "a small number of
> queries" or maybe:

Okay, I agree to update the description.

>>>>       Enabling this parameter may incur a noticeable performance penalty,
>>>>       especially similar queries are run by many concurrent connections and
>>>>       compete to update the same pg_stat_statements entry

"a small number of" is better than "similar" at the above because
"similar" sounds a bit unclear in this case?

It's better to use "entries" rather than "entry" at the above?

Regards,
  

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