On 2014-08-26 08:12:48 +0200, Fabien COELHO wrote: > As for checkpoint spreading, raising checkpoint_completion_target to 0.9 > degrades the situation (20% of transactions are more than 200 ms late > instead of 10%, bgwriter wrote less that 1 page per second, on on 500s run). > So maybe there is a bug here somewhere.
What are the other settings here? checkpoint_segments, checkpoint_timeout, wal_buffers? Could you show the output of log_checkpoints during that run? Checkpoint spreading only works halfway efficiently if all checkpoints are triggered by "time" and not by "xlog". 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
