diff options
| author | Heikki Linnakangas <heikki.linnakangas@iki.fi> | 2013-01-17 20:23:00 +0200 |
|---|---|---|
| committer | Heikki Linnakangas <heikki.linnakangas@iki.fi> | 2013-01-17 20:23:00 +0200 |
| commit | 0b6329130e8e4576e97ff763f0e773347e1a88af (patch) | |
| tree | 7902ba1fa99ac8124232122ce16231cff0b0e21e /src/backend/access/transam/timeline.c | |
| parent | 8ae35e91807508872cabd3b0e8db35fc78e194ac (diff) | |
Make pg_receivexlog and pg_basebackup -X stream work across timeline switches.
This mirrors the changes done earlier to the server in standby mode. When
receivelog reaches the end of a timeline, as reported by the server, it
fetches the timeline history file of the next timeline, and restarts
streaming from the new timeline by issuing a new START_STREAMING command.
When pg_receivexlog crosses a timeline, it leaves the .partial suffix on the
last segment on the old timeline. This helps you to tell apart a partial
segment left in the directory because of a timeline switch, and a completed
segment. If you just follow a single server, it won't make a difference, but
it can be significant in more complicated scenarios where new WAL is still
generated on the old timeline.
This includes two small changes to the streaming replication protocol:
First, when you reach the end of timeline while streaming, the server now
sends the TLI of the next timeline in the server's history to the client.
pg_receivexlog uses that as the next timeline, so that it doesn't need to
parse the timeline history file like a standby server does. Second, when
BASE_BACKUP command sends the begin and end WAL positions, it now also sends
the timeline IDs corresponding the positions.
Diffstat (limited to 'src/backend/access/transam/timeline.c')
| -rw-r--r-- | src/backend/access/transam/timeline.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/src/backend/access/transam/timeline.c b/src/backend/access/transam/timeline.c index 46379bbff88..ad4f3162c53 100644 --- a/src/backend/access/transam/timeline.c +++ b/src/backend/access/transam/timeline.c @@ -545,22 +545,26 @@ tliOfPointInHistory(XLogRecPtr ptr, List *history) } /* - * Returns the point in history where we branched off the given timeline. - * Returns InvalidXLogRecPtr if the timeline is current (= we have not - * branched off from it), and throws an error if the timeline is not part of - * this server's history. + * Returns the point in history where we branched off the given timeline, + * and the timeline we branched to (*nextTLI). Returns InvalidXLogRecPtr if + * the timeline is current, ie. we have not branched off from it, and throws + * an error if the timeline is not part of this server's history. */ XLogRecPtr -tliSwitchPoint(TimeLineID tli, List *history) +tliSwitchPoint(TimeLineID tli, List *history, TimeLineID *nextTLI) { ListCell *cell; + if (nextTLI) + *nextTLI = 0; foreach (cell, history) { TimeLineHistoryEntry *tle = (TimeLineHistoryEntry *) lfirst(cell); if (tle->tli == tli) return tle->end; + if (nextTLI) + *nextTLI = tle->tli; } ereport(ERROR, |