Re: Upgrade from PG12 to PG

On Jul 20, 2023, at 7:23 AM, Jef Mortelle <jefmortelle@gmail.com> wrote:
> I use /usr/lib/postgresql15/bin/pg_upgrade -v -p 5431 -P 5432
>
> I takes a lot of time, more than 6 hours

I'm in the middle of a similar database migration myself, but I'm coming from 10.23.

Have you considered adding the --link and --jobs=NN (where NN is the number of CPU cores on your server minus 2 or
somethinglike that) to your pg_upgrade command? I wonder if that would speed things up significantly. 

Also, if your file system supports reflinks (Linux kernel 4.5 and XFS with reflink support activated or Btrfs or macOS
APFS),then use --clone instead of --link. 

Good luck,
Ed