Hi, Looking at the XLogInsert() from 8.3 and 8.4, the 8.4 version includes a call to RecoveryInProgress() at the top as well as a call to TRACE_POSTGRESQL_XLOG_INSERT(). Could either of those have caused a context switch or cache flush resulting in worse performance. Cheers, Ken -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance