Re: Synchronization levels in SR

On May 27, 2010, at 4:31 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> Heikki Linnakangas wrote:
>> BTW, I think we're going to need a separate config file for listing
>> the
>> standbys anyway. There you can write per-server rules and options,
>> but
>> explicitly knowing about all the standbys also allows the master to
>> recycle WAL as soon as it has been streamed to all the registered
>> standbys. Currently we just keep wal_keep_segments files around,
>> just in
>> case there's a standby out there that needs them.
>
> Ideally we could set 'slave_sync_count' and
> 'slave_commit_continue_mode'
> on the master, and allow the sync/async mode to be set on each slave,
> e.g. if slave_sync_count = 2 and slave_commit_continue_mode = #2, then
> two slaves with sync mode of #2 or stricter have to complete before
> the
> master can continue.
>
> Naming the slaves on the master seems very confusing because I am
> unclear how we would identify named slaves, and the names have to
> match,
> etc.

The names could be configured with a GUC on the slaves, or we could
base it on the login role.

...Robert