Introduce Streaming Replication.

This includes two new kinds of postmaster processes, walsenders and
walreceiver. Walreceiver is responsible for connecting to the primary server
and streaming WAL to disk, while walsender runs in the primary server and
streams WAL from disk to the client.

Documentation still needs work, but the basics are there. We will probably
pull the replication section to a new chapter later on, as well as the
sections describing file-based replication. But let's do that as a separate
patch, so that it's easier to see what has been added/changed. This patch
also adds a new section to the chapter about FE/BE protocol, documenting the
protocol used by walsender/walreceivxer.

Bump catalog version because of two new functions,
pg_last_xlog_receive_location() and pg_last_xlog_replay_location(), for
monitoring the progress of replication.

Fujii Masao, with additional hacking by me

1 files changed, 4 insertions, 4 deletions

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index dd7da742d22..bf1234614c9 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.314 2010/01/06 03:04:00 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.315 2010/01/15 09:19:01 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -7044,10 +7044,10 @@ copy_relation_data(SMgrRelation src, SMgrRelation dst,
 	Page		page = (Page) buf;
 
 	/*
-	 * We need to log the copied data in WAL iff WAL archiving is enabled AND
-	 * it's not a temp rel.
+	 * We need to log the copied data in WAL iff WAL archiving/streaming is
+	 * enabled AND it's not a temp rel.
 	 */
-	use_wal = XLogArchivingActive() && !istemp;
+	use_wal = XLogIsNeeded() && !istemp;
 
 	nblocks = smgrnblocks(src, forkNum);