On Mon, Dec 6, 2021 at 7:53 PM Ashutosh Sharma <ashu.coe...@gmail.com> wrote: > > Thank you, Dilip for the quick response. I am okay with the changes done in > the v7 patch. > > One last point - If we try to clone a huge database, as expected CREATE > DATABASE emits a lot of WALs, causing a lot of intermediate checkpoints which > seems to be affecting the performance slightly.
Yeah, that is a valid point because instead of just one WAL for createdb we will generate WAL for each page in the database, so I agree that if the max_wal_size is not enough for those WALs then we might have to pay the cost of multiple checkpoints. However, if we compare it with the current mechanism then now it is a forced checkpoint and there is no way to avoid it whereas with the new approach user can set enough max_wal_size and they can avoid it. So in other words now the checkpoint is driven by the amount of resource which is true for any other operation e.g. ALTER TABLE SET TABLESPACE so now it is in more sync with the rest of the system, but without the patch, it was a special purpose forced checkpoint only for the createdb. -- Regards, Dilip Kumar EnterpriseDB: http://www.enterprisedb.com
