On 2014-10-02 10:56:05 -0400, Robert Haas wrote: > On Thu, Oct 2, 2014 at 10:44 AM, Andres Freund <and...@2ndquadrant.com> wrote: > > On 2014-10-02 10:40:30 -0400, Robert Haas wrote: > >> On Thu, Oct 2, 2014 at 10:36 AM, Andres Freund <and...@2ndquadrant.com> > >> wrote: > >> >> OK. > >> > > >> > Given that the results look good, do you plan to push this? > >> > >> By "this", you mean the increase in the number of buffer mapping > >> partitions to 128, and a corresponding increase in MAX_SIMUL_LWLOCKS? > > > > Yes. Now that I think about it I wonder if we shouldn't define > > MAX_SIMUL_LWLOCKS like > > #define MAX_SIMUL_LWLOCKS (NUM_BUFFER_PARTITIONS + 64) > > or something like that? > > Nah. That assumes NUM_BUFFER_PARTITIONS will always be the biggest > thing, and I don't see any reason to assume that, even if we're making > it true for now.
The reason I'm suggesting is that NUM_BUFFER_PARTITIONS (and NUM_LOCK_PARTITIONS) are the cases where we can expect many lwlocks to be held at the same time. It doesn't seem friendly to users experimenting with changing this to know about a define that's private to lwlock.c. But I'm fine with doing this not at all or separately - there's no need to actually do it together. 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
