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Re: sql execution time in pg_stat_statements - Mailing list pgsql-performance

From Julien Rouhaud
Subject Re: sql execution time in pg_stat_statements
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Msg-id CAOBaU_Z=+-SeHeG4wBOLUEAYs+ngrtFYUTUyE0RATLZ-RJ=AjA@mail.gmail.com
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In response to RE: sql execution time in pg_stat_statements  ("Michel SALAIS" <msalais@msym.fr>)
List pgsql-performance
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On Sat, Sep 11, 2021 at 1:12 AM Michel SALAIS <msalais@msym.fr> wrote:
>
> I thaught that total_time (total_exec_time + total_plan_time) included I/O but when we have blk_read_time +
blk_write_time equals several times total_time it is difficult to continue to think that...
 

Maybe not that difficult.  If the queries use parallelism, the query
total execution time may be say 1 second, but if there were X workers
it could actually cumulate X+1 seconds of execution time, and
therefore reach more than 1 second of cumulated read/write time.

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