Re: A micro-optimisation for walkdir()

On Mon, Sep 14, 2020 at 12:42 AM Thomas Munro <thomas(dot)munro(at)gmail(dot)com>
wrote:

> On Tue, Sep 8, 2020 at 10:53 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Thomas Munro <thomas(dot)munro(at)gmail(dot)com> writes:
> > > FWIW I just spotted a couple of very suspicious looking failures for
> > > build farm animal "walleye", a "MinGW64 8.1.0" system, that say:
> >
> > walleye's been kind of unstable since the get-go, so I wouldn't put
> > too much faith in reports just from it.
>
> CC'ing animal owner.
>
> <pokes at the logs> I suspect that someone who knows about PostgreSQL
> on Windows would recognise the above symptom, but my guess is the
> Windows "indexing" service is on, or an antivirus thing, or some other
> kind of automatically-open-and-sniff-every-file-on-certain-file-events
> thing. It looks like nothing of ours is even running at that moment
> ("waiting for server to shut down.... done"), and it's the RMDIR /s
> shell command that is reporting the error. The other low probability
> error seen on this host is this one:
>
> +ERROR: could not stat file "pg_wal/000000010000000000000007":
> Permission denied
>

This is a known problem, previous to this patch. There have been a couple
of attempts to tackle it, and hopefully the shared-memory based stats
collector will take care of it:

https://www.postgresql.org/message-id/18986.1585585020%40sss.pgh.pa.us

Regards,

Juan José Santamaría Flecha