diff options
| author | Andres Freund <andres@anarazel.de> | 2016-12-22 11:31:50 -0800 |
|---|---|---|
| committer | Andres Freund <andres@anarazel.de> | 2016-12-22 11:31:50 -0800 |
| commit | 6ef2eba3f57f17960b7cd4958e18aa79e357de2f (patch) | |
| tree | 99eb4b00aee1a41081f9b163923ee711b0567aa2 /doc/src | |
| parent | 097e41439d69e11fb870e009b1ac64dda4f01c3d (diff) | |
Skip checkpoints, archiving on idle systems.
Some background activity (like checkpoints, archive timeout, standby
snapshots) is not supposed to happen on an idle system. Unfortunately
so far it was not easy to determine when a system is idle, which
defeated some of the attempts to avoid redundant activity on an idle
system.
To make that easier, allow to make individual WAL insertions as not
being "important". By checking whether any important activity happened
since the last time an activity was performed, it now is easy to check
whether some action needs to be repeated.
Use the new facility for checkpoints, archive timeout and standby
snapshots.
The lack of a facility causes some issues in older releases, but in my
opinion the consequences (superflous checkpoints / archived segments)
aren't grave enough to warrant backpatching.
Author: Michael Paquier, editorialized by Andres Freund
Reviewed-By: Andres Freund, David Steele, Amit Kapila, Kyotaro HORIGUCHI
Bug: #13685
Discussion:
https://www.postgresql.org/message-id/20151016203031.3019.72930@wrigleys.postgresql.org
https://www.postgresql.org/message-id/CAB7nPqQcPqxEM3S735Bd2RzApNqSNJVietAC=6kfkYv_45dKwA@mail.gmail.com
Backpatch: -
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/config.sgml | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 1b98c416e06..b6b20a368ec 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -2852,12 +2852,10 @@ include_dir 'conf.d' parameter is greater than zero, the server will switch to a new segment file whenever this many seconds have elapsed since the last segment file switch, and there has been any database activity, - including a single checkpoint. (Increasing - <varname>checkpoint_timeout</> will reduce unnecessary - checkpoints on an idle system.) - Note that archived files that are closed early - due to a forced switch are still the same length as completely full - files. Therefore, it is unwise to use a very short + including a single checkpoint (checkpoints are skipped if there is + no database activity). Note that archived files that are closed + early due to a forced switch are still the same length as completely + full files. Therefore, it is unwise to use a very short <varname>archive_timeout</> — it will bloat your archive storage. <varname>archive_timeout</> settings of a minute or so are usually reasonable. You should consider using streaming replication, |