On Wed, Feb 13, 2019 at 4:16 AM Peter Eisentraut <peter.eisentr...@2ndquadrant.com> wrote: > Bulk operations like CREATE INDEX, ALTER TABLE, or bulk loads can create > a lot of WAL. A lot of WAL at once can cause delays in replication. > For synchronous replication, this can make seemingly unrelated sessions > hang. But also for asynchronous replication, it will increase latency.
I think that I suggested a feature like this early during my time at Heroku, about 5 years ago. There would occasionally be cases where ops would find it useful to throttle WAL writing using their own terrible kludge (it involved sending SIGSTOP to the WAL writer). I recall that this idea was not well received at the time. I still think it's a good idea, though. Provided there is a safe way to get it to work. -- Peter Geoghegan
