On 12/09/2018 01:10 PM, Stephen Frost wrote:
Greetings,
* Ron (ronljohnsonjr@xxxxxxxxx) wrote:
I've got a full pgbackrest backup in crontab that runs weekly, and a diff
backup that runs nightly. However, I can't find any way to do hourly WAL
backups.
Or does "archive_command = 'pgbackrest --stanza=demo archive-push %p'" just
keep things automatically caught up, obviating the need for periodic WAL
backups (as are needed in other RDBMSs)?
Yes and no. With the archive command, every WAL archived will be pushed
to the archive more-or-less immediately (or, at least, as fast as your
system can get it there, if you enable parallel archiving in
pgbackrest), however, WAL files have a size (by default 16MB) and if you
have a very slowly changing system then it could possibly be hours
between WALs being pushed to the archive by archive_command.
You can address that risk by enabling archive_timeout, which will make
PostgreSQL archive the WAL file even if it isn't full after a certain
amount of time, reducing the potential data loss window.
I thought checkpoint_timeout forced a WAL switch.
--
Angular momentum makes the world go 'round.
