Re: Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review]) - Mailing list pgsql-hackers

From Amit Kapila
Subject Re: Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review])
Date
Msg-id 00cc01ce8f75$95f8cfe0$c1ea6fa0$@kapila@huawei.com
Whole thread Raw
In response to Re: Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review])  (Cédric Villemain <cedric@2ndquadrant.com>)
Responses Re: Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review])  (Stephen Frost <sfrost@snowman.net>)
List pgsql-hackers
On Friday, August 02, 2013 4:17 PM Cédric Villemain wrote:
Le vendredi 2 août 2013 09:23:17, Amit Kapila a écrit :
> On Friday, August 02, 2013 8:57 AM Stephen Frost wrote:
> > * Andres Freund (andres@2ndquadrant.com) wrote:
>> > > FWIW, I think you've just put the final nail in the coffin of this
>> > > patch by raising the barriers unreasonably high.
>> >
>> > For my 2c, I don't think it's an unreasonable idea to actually
>> > *consider* what options are available through this mechanism rather
>> > than just presuming that it's a good idea to be able to modify
>> > anything, including things that you wouldn't be able to fix after a
>> > restart w/o hacking around in $PGDATA.
>
>> I think if user has set any value wrong such that it doesn't allow server
>> to start,
>> we can provide an option similar to pg_resetxlog to reset the auto file.
 
> While guessing what changes are safe is hard, it is easy to discover the
GUCs preventing PostgreSQL from restarting correctly.
> pg_ctl might be able to expose a clear message like :
> MSG: Params X and Y set by ALTER SYSTEM prevent PostgreSQL from starting
> HINT: Issue pg_ctl --ignore-bad-GUC start
 
> Note that the same may also allow postgresql to start with bad GUC value
in postgresql.conf ....
> So this is another topic (IMHO).
 Yes, this can be viable option to ignore variable values that don't allow
server to start, also I agree with you that this can be a separate patch.
 
> With the current idea of one-GUC-one-file in a PGDATA subdirectory it is
*easy* to fix for any DBA or admin.

> However, note that I do prefer a simple
'include_auto_conf=here|start|end|off' in postgresql.conf (by default at end
of file, with value 'end' set).
   Earlier patch has this implementation, but later based on suggestions, I
made it default.

With Regards,
Amit Kapila.




pgsql-hackers by date:

Previous
From: Amit Kapila
Date:
Subject: Re: Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review])
Next
From: Stephen Frost
Date:
Subject: Re: Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review])