On Tue, Apr 11, 2017 at 3:53 PM, Robert Haas <robertmh...@gmail.com> wrote: > 1TB / 8kB per page * 60 tuples/page * 20% * 6 bytes/tuple = 9216MB of > maintenance_work_mem > > So we'll allocate 128MB+256MB+512MB+1GB+2GB+4GB which won't be quite > enough so we'll allocate another 8GB, for a total of 16256MB, but more > than three-quarters of that last allocation ends up being wasted. > I've been told on this list before that doubling is the one true way > of increasing the size of an allocated chunk of memory, but I'm still > a bit unconvinced.
There you're wrong. The allocation is capped to 1GB, so wastage has an upper bound of 1GB. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers