| From: | Julien Rouhaud <rjuju123(at)gmail(dot)com> |
|---|---|
| To: | Michel SALAIS <msalais(at)msym(dot)fr> |
| Cc: | postgres performance list <pgsql-performance(at)postgresql(dot)org> |
| Subject: | Re: sql execution time in pg_stat_statements |
| Date: | 2021-09-10 17:43:06 |
| Message-ID: | CAOBaU_Z=+-SeHeG4wBOLUEAYs+ngrtFYUTUyE0RATLZ-RJ=AjA@mail.gmail.com |
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| Lists: | pgsql-performance |
On Sat, Sep 11, 2021 at 1:12 AM Michel SALAIS <msalais(at)msym(dot)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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