On Thu, Sep 25, 2014 at 9:14 AM, Andres Freund <and...@2ndquadrant.com> wrote: >> Why stop at 128 mapping locks? Theoretical downsides to having more >> mapping locks have been mentioned a few times but has this ever been >> measured? I'm starting to wonder if the # mapping locks should be >> dependent on some other value, perhaps the # of shared bufffers... > > Wrong way round. You need to prove the upside of increasing it further, > not the contrary. The primary downside is cache hit ratio and displacing > other cache entries...
I can't do that because I don't have the hardware. I wasn't suggesting to just set it but to measure the affects of setting it. But the benefits from going from 16 to 128 are pretty significant at least on this hardware; I'm curious how much further it can be pushed...what's wrong with trying it out? merlin -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
