Re: PG 10 streaming replication pg_wal question

ghiureai wrote:
> I am testing PG10 streaming replication ,  with archiving off, I have 
> pg_wal on separate directory  to monitor the growth , I had the slave 
> offline yesterday  for  more than 20h while I was restoring one of db 
> (60GB) with pg_restore from a backup taken with pg_dump, today I brought 
> the slave PG host online and replication catch up  nicely , master and 
> slave are in sync now, but  on master host the pg_wal is still same  
> large size ( as yesterday)  even after all the wal files had been 
> applied to salve, would replication process not suppose to removed the 
> wal files  on master after being applied to salve ?
> ( do I need to manually implement a cleanup job of this wal files, as 
> mentioned archiving is off on  both servers)

Never remove WAL files yourself.

pg_wal will shrink eventually.
At the next checkpoint, PostgreSQL will remove all WAL files
that were completed and archived successfully since the
previous checkpoint, thus reducing WAL size a little.

If there is activity on the databases, pg_wal will eventually
shrink back to max_wal_size.

Yours,
Laurenz Albe