Hi, On 2013-09-17 17:55:01 +0600, Дмитрий Дегтярёв wrote: > We have not been able to reproduce this problem on a test servers. Use this > patch to production servers do not dare. > > In the course of studying the problems we have identified that many queries > are executed on the slave several times slower. On master function > heap_hot_search_buffer execute 100 cycles, on the slave the same query with > the same plan function heap_hot_search_buffer execute 2000 cycles. > Also, we were able to reproduce the problem on the master and detect that > there s_lock of slow queries. What you describe is normally an indication that you have too many longrunning transactions around preventing hot pruning from working. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance