On Fri, Nov 17, 2017 at 5:46 PM, Jeremy Schneider <schnei...@ardentperf.com> wrote: > Having pg_upgrade simply allow an upgrade where the WAL sizes don't match > between the old cluster and the new cluster seems fairly trivial. ... > Writing code to change the WAL size on an existing cluster will be a little > more > complex. We will need to delete all WAL files and recreate them at the new > sizes. We will need to either (1) be absolutely sure that there was a > clean shutdown > or (2) copy WAL data from the old files to the new files.
I think pg_resetwal has most of this logic already. > These two ideas don't seem mutually exclusive to me. If pg_upgrade > allows working > with different WAL sizes, it doesn't mean we can't still introduce a > utility to change the > WAL size on running clusters. I don't think anyone is talking about doing this on a running cluster. But it seems simple enough on a cluster that has been shut down. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company