Re: pg_stat directory and pg_stat_statements

On Thu, May 29, 2014 at 4:55 AM, Tomas Vondra <tv(at)fuzzy(dot)cz> wrote:
> On 28.5.2014 19:52, Fujii Masao wrote:
>> 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?
>
> For HEAD, probably yes. But what about backpatching 9.3?

I think No. So we should not backpatch this to 9.3.

Regards,

--
Fujii Masao