On 2018-Nov-20, Fabien COELHO wrote:
>
> > I didn't quite understand this hunk. Why does it remove the
> > is_latencies conditional? (The preceding comment shown here should be
> > updated obviously if this change is correct, but I'm not sure it is.)
>
> Pgbench runs benches a collects performance data about it.
>
> I simplified the code to always collect data, without trying to be clever
> about cases where these data may not be useful so some collection can be
> skipped.
>
> Here the test avoids recording the statement start time, mostly a simple
> assignment and then later another test avoids recording the stats in the
> same case, which are mostly a few adds.
>
> ISTM that this is over optimization and unlikely to be have any measurable
> effects compared to the other tasks performed when executing commands, so a
> simpler code is better.
I don't think we're quite ready to buy this argument just yet.
See https://www.postgresql.org/message-id/flat/31856.1400021891@sss.pgh.pa.us
--
Álvaro Herrera https://www.2ndQuadrant.com/
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