Re: Statement timeout

On 3 June 2016 at 09:45, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:

> > Well, multiple parse/bind/execute messages before a sync are definitely
> > used by PgJDBC and nPgSQL for batching,
>
> Yes, I realized in JDBC.
>
> > and I just posted a patch for it
> > for libpq.
>
> I didn't noticed it. Could you give me the message id or URL?
>
>
https://commitfest.postgresql.org/10/634/

https://www.postgresql.org/message-id/flat/CAMsr+YFUjJytRyV4J-16bEoiZyH=4nj+sQ7JP9ajwz=B4dMMZw(at)mail(dot)gmail(dot)com#CAMsr+YFUjJytRyV4J-16bEoiZyH=4nj+sQ7JP9ajwz=B4dMMZw@mail.gmail.com

> > I am very surprised to find out that statement_timeout tracks the total
> > time and isn't reset by a new statement, but I guess it makes sense -
> what,
> > exactly, delimits a "query" in extended query mode? statement_timeout in
> > simple-query mode starts at parse time and runs until the end of execute.
> > In e.q.p. there might be only one parse, then a series of Bind and
> Execute
> > messages, or there may be repeated Parse messages.
>
> Another issue is inconsistency with log duration, which shows the the
> elapsed time for each execute message. I think statement timeout
> should be consistent with statement duration. Otherwise users will be
> confused.
>

While I agree that's confusing, I think that's actualyl a problem with
log_duration.

log_duration is really more of an internal trace parameter that should be
named debug_log_duration or something IMO. It also fails to print the
message type, which makes it even more confusing since it for a typical
extended protocl query it usually logs 3 durations with no indication of
which is what.

Users should be using log_min_duration_statement. You know, the confusingly
named one. Or is it log_duration_min_statement or
log_statement_min_duration or ...?

Yeah, log_duration is confusing to the point I think it needs a comment
like "To record query run-time you probably want
log_min_duration_statement, not log_duration".

--
Craig Ringer http://www.2ndQuadrant.com/
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