Re: Unfortunate choice of short switch name in pgbench

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Tue, Feb 25, 2014 at 2:49 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> To fix this, I propose removing the -P short form and only allowing the
>> long --progress form. I won't argue that this feature is completely
>> useless, but for sure it's not something I'd want more often than once
>> in a blue moon. So I think it does not need to have a short form; and
>> for sure it doesn't need a short form that's so easily confused with a
>> commonly used switch.

> Hmm. I don't have a real specific opinion on the value of this
> particular --progress option, but my experience is that most
> --progress options get a lot of use.

Meh. A progress-reporting feature has use when the tool is working
towards completion of a clearly defined task. In the case of pgbench,
if you told it to run for -T 60 seconds rather than -T 10 seconds,
that's probably because you don't trust a 10-second average to be
sufficiently reproducible. So I'm not real sure that reporting averages
over shorter intervals is all that useful; especially not if it takes
cycles out of pgbench, which itself is often a bottleneck.

I could see some value in a feature that computed shorter-interval TPS
averages and then did some further arithmetic, like measuring the standard
deviation of the shorter-interval averages to assess how much noise there
will be in the full-run average. But that's not what this does, and if it
did do that, "reporting progress" would not be what I'd see as its main
purpose.

regards, tom lane