May i know which setting in postgres controls the size and number of wal files kept in pg_wal directory? We have 245 wal files and total size is 3.5GB
We do NOT have replication in place
So how are you doing WAL archiving for backups? Because most likely that is broken and thus PostgreSQL doesn't feel safe in removing the unarchived WAL.
we are using
Pg 12.7
max_wal_size 16G
That seems a bit excessive...and above your current usage so it is possible you simply need that many segments given the volume of WAL your server produces (you omitted mentioning the time frame for the WAL)
wal_keep_segments 8
You don't have replication in place so wal_keep_segments, a replication GUC, is immaterial here.