Fujii Masao wrote: > On Wed, Jul 8, 2009 at 4:00 AM, Heikki > Linnakangas<heikki.linnakan...@enterprisedb.com> wrote: >>> I would envision the slaves >>> connecting to the master's replication port and asking "feed me WAL >>> beginning at LSN position thus-and-so", with no notion of WAL file >>> boundaries exposed anyplace. >> Yep, that's the way I envisioned it to work in my protocol suggestion >> that Fujii adopted >> (http://archives.postgresql.org/message-id/4951108a.5040...@enterprisedb.com). >> The <begin> and <end> values are XLogRecPtrs, not WAL filenames. > > If <begin> indicates the middle of the XLOG file, the file written to the > standby is partial. Is this OK? After two server failed, the XLOG file > including <begin> might still be required for crash recovery of the > standby server. But, since it's partial, the crash recovery would fail. > I think that any XLOG file should be written to the standby as it can > be replayed by a normal recovery.
The standby can store the streamed WAL to files in pg_xlog of the standby, to facilitate crash recovery, but it doesn't need to be exposed in the protocol. -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
