Re: remove pg_standby?

On Mon, Mar 2, 2015 at 8:37 PM, Heikki Linnakangas <hlinnaka(at)iki(dot)fi> wrote:
> On 03/02/2015 11:53 AM, Fujii Masao wrote:
>>
>> On Sat, Feb 28, 2015 at 5:00 AM, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
>>>
>>> On 11/10/2014 10:54 AM, Magnus Hagander wrote:
>>>>
>>>> On Mon, Nov 10, 2014 at 7:48 PM, Heikki Linnakangas
>>>> <hlinnakangas(at)vmware(dot)com> wrote:
>>>>>
>>>>> pg_standby is more configurable than the built-in standby_mode=on. You
>>>>> can
>>>>> set the sleep time, for example, while standby_mode=on uses a
>>>>> hard-coded
>>>>> delay of 5 s. And pg_standby has a configurable maximum wait time. And
>>>>> as
>>>>> Fujii pointed out, the built-in system will print an annoying message
>>>>> to the
>>>>> log every time it attempts to restore a file. Nevertheless, 99% of
>>>>> users
>>>>> would probably be happy with the built-in thing.
>>>>
>>>>
>>>> As long as pg_standby has features that are actually useful and that
>>>> are not in the built-in system, we shouldn't remove it. We should,
>>>> however, try to fix those in the main system so we can get rid of it
>>>> after that :)
>>>
>>>
>>> As of current 9.5, we have configurable retries and standby delay in
>>> mainstream. Is there some reason we still need pg_standby?
>>
>>
>> Yes, it's not easy to perform "fast failover" without pg_standby for now.
>
>
> What is "fast failover"?

Per document,

------------------
In fast failover, the server is brought up immediately. Any WAL files
in the archive that have not yet been applied will be ignored, and all
transactions in those files are lost. To trigger a fast failover,
create a trigger file and write the word fast into it. pg_standby can
also be configured to execute a fast failover automatically if no new
WAL file appears within a defined interval.
------------------

Regards,

--
Fujii Masao