Re: BUG #16497: old and new pg_controldata WAL segment sizes areinvalid or do not match

On Thu, Jun 18, 2020 at 11:41:53AM -0400, Stephen Frost wrote:
> Sure, most options to initdb need to be the same between the old cluster
> and the new cluster, but this specific option doesn't have to be, since
> we require that it's a cleanly shut down cluster, so why are we
> complaining about it if it's different..?

Did you not read my previous email that we might have added this so we
can upgrade replicas?  I am sure I can dig out the commit that added
this and find the original cause, but running pg_upgrade on replicas is
enough of a reason to me.  Yeah, we could add a flag to pg_upgrade to
allow this if you are not upgrading replicas, but why bother?  It might
even work if you create the new replicas with the same WAL segment size,
but why add complexity for pg_upgrade, which is already complex enough.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EnterpriseDB                             https://enterprisedb.com

  The usefulness of a cup is in its emptiness, Bruce Lee