On 2021-06-16 17:36, Dean Gibson (DB Administrator) wrote:
Is this reasonable thinking?
I'd think that one would want a *wal_keep_size* to cover the pending
updates while the standby server might be unavailable, however long
one might anticipate that would be.
In my case, I get a complete replacement (in the form of "|"-
delimited ASCII files) of one of the SCHEMAs every Sunday. The size
of that ASCII data is about 2GB, so I'm thinking of doubling that to
4GB (256 WAL files) to protect me in the case of the standby being
unavailable during the update. Note that a complete loss of both
servers is not catastrophic (I have backups); it would just be annoying.
In the absence of any clear guidance, I temporarily set wal_keep_size to
16GB & waited for the Sunday update. That update today created just
over 6GB of WAL files during the update, so I've set wal_keep_size to
8GB (512 WAL files).
Oh, and wal_keep_size is NOT an upper limit restricting further WAL
files. It's more like a minimum.
