Re: Synchronous replication

On Sun, Aug 1, 2010 at 10:08 PM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
> On Sun, Aug 1, 2010 at 9:30 PM, Greg Stark <gsstark(at)mit(dot)edu> wrote:
>> This doesn't have to be done manually.
>
> Agreed, if we register standbys in the master.
>
>> The streaming protocol could
>> include the standby sending its system id to the master. The master
>> could just keep a list of system ids with the last record they've been
>> sent and the last they've confirmed receipt, fsync, application,
>> whatever the protocol covers. If the same system reconnects it just
>> overwrites the existing data for that system id.
>
> Since every standby has the same system id, we cannot distinguish
> them by that id. ISTM that the master should assign the unique id
> for each standby, and they should save it in pg_control.

Another option might be to let the user name them.

standby_name='near'
standby_name='far1'
standby_name='far2'

...or whatever.

--
Robert Haas
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