Re: Proposal for changes to recovery.conf API

On Tue, Dec 20, 2016 at 7:11 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On 19 December 2016 at 21:29, Peter Eisentraut
> <peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:
>> On 12/16/16 8:52 PM, Robert Haas wrote:
>>> If the explanation is just a few sentences long, I see no reason not
>>> to include it in the release notes.
>>
>> As far as I can tell from the latest posted patch, the upgrade
>> instructions are
>>
>> - To trigger recovery, create an empty file recovery.trigger instead of
>> recovery.conf.
>>
>> - All parameters formerly in recovery.conf are now regular
>> postgresql.conf parameters. For backward compatibility, recovery.conf
>> is read after postgresql.conf, but the parameters can now be put into
>> postgresql.conf if desired.
>>
>> Some of that might be subject to patch review, but it's probably not
>> going to be much longer than that. So I think that will fit well into
>> the usual release notes section.
>
> Although that's right, there is more detail.
>
> The current list is this... based upon discussion in Tokyo dev meeting
>
> * Any use of the earlier recovery.conf or any of the old recovery
> parameter names causes an ERROR, so we have a clear API break
>
> * To trigger recovery, create an empty recovery.trigger file. Same as
> recovery.conf with standby_mode = off
>
> * To trigger standby, create an empty standby.trigger file. Same as
> recovery.conf with standby_mode = on

API for crash recovery will never be changed. That is, crash recovery needs
neither recovery.trigger nor standby.trigger. When the server starts a crash
recovery without any trigger file, any recovery parameter settings in
postgresql.conf are ignored. Right?

Regards,

--
Fujii Masao