Commit Graph

13 Commits

Author SHA1 Message Date
Heikki Linnakangas b186523fd9 Send status updates back from standby server to master, indicating how far
the standby has written, flushed, and applied the WAL. At the moment, this
is for informational purposes only, the values are only shown in
pg_stat_replication system view, but in the future they will also be needed
for synchronous replication.

Extracted from Simon riggs' synchronous replication patch by Robert Haas, with
some tweaking by me.
2011-02-10 21:04:02 +02:00
Magnus Hagander 507069de6d Add option to include WAL in base backup
When included, this makes the base backup a complete working
"clone" of the initial database, ready to have a postmaster
started against it without the need to set up any log archiving
or similar.

Magnus Hagander, reviewed by Fujii Masao and Heikki Linnakangas
2011-01-30 21:30:09 +01:00
Magnus Hagander fcd810c69a Use a lexer and grammar for parsing walsender commands
Makes it easier to parse mainly the BASE_BACKUP command
with it's options, and avoids having to manually deal
with quoted identifiers in the label (previously broken),
and makes it easier to add new commands and options in
the future.

In passing, refactor the case statement in the walsender
to put each command in it's own function.
2011-01-14 16:30:33 +01:00
Magnus Hagander 688423d004 Exit from base backups when shutdown is requested
When the exit waits until the whole backup completes, it may take
a very long time.

In passing, add back an error check in the main loop so we detect
clients that disconnect much earlier if the backup is large.
2011-01-14 12:36:45 +01:00
Magnus Hagander 4c8e20f815 Track walsender state in shared memory and expose in pg_stat_replication 2011-01-11 21:25:28 +01:00
Itagaki Takahiro a755ea33ae New system view pg_stat_replication displays activity of wal sender processes.
Itagaki Takahiro and Simon Riggs.
2011-01-07 20:35:38 +09:00
Bruce Momjian 5d950e3b0c Stamp copyrights for year 2011. 2011-01-01 13:18:15 -05:00
Magnus Hagander 9f2e211386 Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
Heikki Linnakangas 2746e5f21d Introduce latches. A latch is a boolean variable, with the capability to
wait until it is set. Latches can be used to reliably wait until a signal
arrives, which is hard otherwise because signals don't interrupt select()
on some platforms, and even when they do, there's race conditions.

On Unix, latches use the so called self-pipe trick under the covers to
implement the sleep until the latch is set, without race conditions. On
Windows, Windows events are used.

Use the new latch abstraction to sleep in walsender, so that as soon as
a transaction finishes, walsender is woken up to immediately send the WAL
to the standby. This reduces the latency between master and standby, which
is good.

Preliminary work by Fujii Masao. The latch implementation is by me, with
helpful comments from many people.
2010-09-11 15:48:04 +00:00
Itagaki Takahiro 147c665d01 Remove prototype of GetOldestWALSendPointer(), that is marked as NOT_USED. 2010-06-17 00:06:34 +00:00
Heikki Linnakangas 9b8a73326e Introduce wal_level GUC to explicitly control if information needed for
archival or hot standby should be WAL-logged, instead of deducing that from
other options like archive_mode. This replaces recovery_connections GUC in
the primary, where it now has no effect, but it's still used in the standby
to enable/disable hot standby.

Remove the WAL-logging of "unlogged operations", like creating an index
without WAL-logging and fsyncing it at the end. Instead, we keep a copy of
the wal_mode setting and the settings that affect how much shared memory a
hot standby server needs to track master transactions (max_connections,
max_prepared_xacts, max_locks_per_xact) in pg_control. Whenever the settings
change, at server restart, write a WAL record noting the new settings and
update pg_control. This allows us to notice the change in those settings in
the standby at the right moment, they used to be included in checkpoint
records, but that meant that a changed value was not reflected in the
standby until the first checkpoint after the change.

Bump PG_CONTROL_VERSION and XLOG_PAGE_MAGIC. Whack XLOG_PAGE_MAGIC back to
the sequence it used to follow, before hot standby and subsequent patches
changed it to 0x9003.
2010-04-28 16:10:43 +00:00
Bruce Momjian 65e806cba1 pgindent run for 9.0 2010-02-26 02:01:40 +00:00
Heikki Linnakangas 40f908bdcd 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
2010-01-15 09:19:10 +00:00