Re: pg_stat directory and pg_stat_statements

On Thu, May 29, 2014 at 12:37 AM, Peter Geoghegan <pg(at)heroku(dot)com> wrote:
> On Wed, May 28, 2014 at 7:01 AM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
>> But pg_stat_statements file is saved under $PGDATA/global yet.
>> Is this intentional or just oversight?
>
>
> I think it's an oversight.

OK, patch attached.

I'm afraid that it's not okay to change the file layout in $PGDATA at this beta1
stage because that change basically seems to need initdb. Otherwise something
like "no such file or directory" error can happen. But in this case what we need
to change is only the location of the pg_stat_statements permanent stats file.
So, without initdb, the server will not be able to find the
pg_stat_statements stats
file, but this is not so harmful. Only the problem is that the
pg_stat_statements
stats which were collected in past would disappear. OTOH, the server can keep
running successfully from then and no critical data will not
disappear. Therefore
I think we can commit this patch even at beta1. Thought?

Regards,

--
Fujii Masao