On Sat, Aug 9, 2014 at 3:03 PM, Michael Paquier <michael.paqu...@gmail.com> wrote: > Hi all, > > Please find attached a patch to add support of synchronous replication > for multiple standby servers. This is controlled by the addition of a > new GUC parameter called synchronous_standby_num, that makes server > wait for transaction commit on the first N standbys defined in > synchronous_standby_names. The implementation is really > straight-forward, and has just needed a couple of modifications in > walsender.c for pg_stat_get_wal_senders and syncrep.c.
Great! This is really the feature which I really want. Though I forgot why we missed this feature when we had added the synchronous replication feature, maybe it's worth reading the old discussion which may suggest the potential problem of N sync standbys. I just tested this feature with synchronous_standby_num = 2. I started up only one synchronous standby and ran the write transaction. Then the transaction was successfully completed, i.e., it didn't wait for two standbys. Probably this is a bug of the patch. And, you forgot to add the line of synchronous_standby_num to postgresql.conf.sample. Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
