Re: checkpointer continuous flushing

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.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services