Hi hackers, The thread for the recent change to allow setting the WAL segment size at initdb time  included a bit of discussion regarding pg_upgrade , where it was suggested that relaxing an error check (presumably in check_control_data()) might be enough to upgrade servers to a different WAL segment size.
We've had success with our initial testing of upgrades to larger WAL segment sizes, including post-upgrade pgbench runs. Beyond adjusting check_control_data(), it looks like the 'pg_resetwal -l' call in copy_xact_xlog_xid() may need to be adjusted to ensure that the WAL starting address is set to a valid value. Allowing changes to the WAL segment size during pg_upgrade seems like a nice way to avoid needing a dump and load, so I would like to propose adding support for this. I'd be happy to submit patches for this in the next commitfest. Nathan  https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=fc49e24fa69a15efacd5b8958115ed9c43c48f9a  https://www.postgresql.org/message-id/20160826043926.pwkz45ksxpmfn4g6%40alap3.anarazel.de -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers