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From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Iwata, Aya" <iwata.aya@jp.fujitsu.com>
cc: "'Yugo Nagata'" <nagata@sraoss.co.jp>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: libpq debug log
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Comments: In-reply-to "Iwata, Aya" <iwata.aya@jp.fujitsu.com>
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"Iwata, Aya" <iwata.aya@jp.fujitsu.com> writes:
> The purpose of this log acquisition I thought is to identify where is th=
e problem: =

> server side, application side or traffic. =


TBH, I think the sort of logging you're proposing would be expensive
enough that *it* would be the bottleneck in a lot of cases.  A lot
of people find that the existing server-side "log_statement" support
is too expensive to keep turned on in production --- and that logs only
received SQL queries, not the returned data, and certainly not every
message passed over the wire.

			regards, tom lane