Re: [PATCH] add --throttle option to pgbench

Fabien COELHO <coelho@cri.ensmp.fr> writes:
> Please find attached a small patch to add a throttling capability to 
> pgbench, that is pgbench aims at a given client transaction rate instead 
> of maximizing the load. The throttling relies on Poisson-distributed 
> delays inserted after each transaction.

I'm having a hard time understanding the use-case for this feature.
Surely, if pgbench is throttling its transaction rate, you're going
to just end up measuring the throttle rate.

> I wanted that to test the impact of various load levels, and for 
> functionnal tests on my laptop which should not drain the battery.

How does causing a test to take longer result in reduced battery drain?
You still need the same number of transactions if you want an honest
test, so it seems to me the machine would have to be on longer and thus
you'd eat *more* battery to get an equivalently trustworthy result.
        regards, tom lane