On 2016-01-20 12:16:24 -0300, Alvaro Herrera wrote: > Andres Freund wrote: > > > The relevant thread is at > > http://archives.postgresql.org/message-id/CA%2BTgmoaCr3kDPafK5ygYDA9mF9zhObGp_13q0XwkEWsScw6h%3Dw%40mail.gmail.com > > what I didn't remember is that I voiced concern back then about exactly > > this: > > http://archives.postgresql.org/message-id/201112011518.29964.andres%40anarazel.de > > ;) > > Interesting. If we consider for a minute that part of the cause for the > slowdown is slowness in pg_clog, maybe we should reconsider the initial > decision to flush as quickly as possible (i.e. adopt a strategy where > walwriter sleeps a bit between two flushes) in light of the group-update > feature for CLOG being proposed by Amit Kapila in another thread -- it > seems that these things might go hand-in-hand.
I don't think it's strongly related - the contention here is on read access to the clog, not on write access. While Amit's patch will reduce the impact of that a bit, I don't see it making a fundamental difference. Andres -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers