On 2015-12-09 19:36:11 +0900, Michael Paquier wrote: > On Wed, Dec 9, 2015 at 4:41 PM, Andres Freund <and...@anarazel.de> wrote: > > On 2015-12-09 16:30:47 +0900, Michael Paquier wrote: > >> > I'm kinda wondering if it wouldn't have been better to go through shared > >> > buffers in ResetUnloggedRelationsInDbspaceDir() instead of using > >> > copy_file(). > >> > >> For deployment with large shared_buffers settings, wouldn't that be > >> actually more costly than the current way of doing? We would need to > >> go through all the buffers at least once and look for the INIT_FORKNUM > >> present to flush them. > > > > We could just check the file sizes on disk, and the check for the > > contents of all the pages for each file. > > By doing it at replay, the flushes are spread across time. And by > doing it at the end of recovery, all the flushes would be grouped. Do > you think that's fine?
The point is that we'd no flushes, because the data would come directly from shared buffers... -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
