Re: Reducing pg_ctl's reaction time

On Mon, Jun 26, 2017 at 7:13 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> The attached proposed patch adjusts pg_ctl to check every 100msec,
> instead of every second, for the postmaster to be done starting or
> stopping. This cuts the runtime of the recovery TAP tests from around
> 4m30s to around 3m10s on my machine, a good 30% savings. I experimented
> with different check frequencies but there doesn't seem to be anything
> to be gained by cutting the delay further (and presumably, it becomes
> counterproductive at some point due to pg_ctl chewing too many cycles).

I see with a 2~3% noise similar improvements on my laptop with
non-parallel tests. That's nice.

+#define WAITS_PER_SEC 10 /* should divide 1000000 evenly */
As a matter of style, you could define 1000000 as well in a variable
and refer to the variable for the division.

> Barring objections I'd like to push this soon.

This also pops up more easily failures with 001_stream_rep.pl without
a patch applied from the other recent thread, so this patch had better
not get in before anything from
https://www.postgresql.org/message-id/8962.1498425057@sss.pgh.pa.us.
--
Michael