On 2014-06-09 08:59:03 -0700, Kevin Grittner wrote: > > *) There is a lot of advice floating around (for example here: > > http://frosty-postgres.blogspot.com/2012/08/postgresql-numa-and-zone-reclaim-mode.html > > ) > > to instruct operators to disable zone_reclaim. Will your changes > > invalidate any of that advice? > > I expect that it will make the need for that far less acute, > although it is probably still best to disable zone_reclaim (based > on the documented conditions under which disabling it makes sense).
I think it'll still be important unless you're running an OLTP workload (i.e. minimal per backend allocations) and your entire workload fits into shared buffers. What zone_reclaim > 0 essentially does is to never allocate memory from remote nodes. I.e. it will throw away all numa node local OS cache to satisfy a memory allocation (including pagefaults). I honestly wouldn't expect this to make a huge difference *wrt* zone_reclaim_mode. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
