On Fri, 2008-10-31 at 13:14 -0400, Tom Lane wrote: > Heikki Linnakangas <[EMAIL PROTECTED]> writes: > > archive_mode = on disables the optimization to skip WAL-logging when > > loading into a new table that was created in the same transaction. > > ... and affects a whole bunch of other behaviors too, in processes all > across the database that could not possibly adopt a new setting > synchronously. That's exactly why it was made a postmaster-start option > to begin with. Simon's given no argument at all why it would be safe to > flip it on-the-fly.
First, you are right my initial sketch missed a couple of obvious mechanisms. But those aren't correctness issues. Flipping in mid-execution wasn't really what I was proposing. That would clearly be a big problem. Even between statements could be a problem. The number of places that test XLogArchivingActive() is fairly small and infrequently executed, so it would be OK to check a shared memory value at those points and retain the setting for the rest of the transaction. Anyway, I think this is worth fixing before release but it clearly isn't worth attempting to rush a patch in the next few hours. I don't think we'll find anyone who is happy with making it a restart-required option. -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
