Re: pgbench throttling latency limit

Hello Andres,

>> pgbench postgres -M prepared -c 72 -j 72 -P 5 -T 3600 -R40000 -L100
>
>> progress: 365.0 s, 18392.1 tps, lat 94.857 ms stddev 23.917, lag 90.980 ms, 106244 skipped
>>
>> 100k skipped transactions at a rate limit of 40k? That doesn't seem right.
>
> Argh. It's just because I used -P5. It's a bit confusing that the other
> options are per second, and this is per interval...

I agree, but I'm unsure of a fix, beyond what is already done which is to
show units next to the figures...

ISTM that people expect "tps" for performance, even on several seconds.
When it comes to skipped transactions, a count seemed more natural. I
really just see this as an indicator that things are not going smoothly.

Maybe it could be shown as a percentage of scheduled transactions,
possibly with an option?

A mitigation is to always run with -P 1 :-).

--
Fabien.