I wrote:
> One thing to look at is the rate of WAL generation for a set number of
> transactions. Maybe the later releases are generating more WAL due to
> multixacts, for instance (prior to 9.3 these weren't wal-logged.)
FWIW a very easy way to measure this is to look at the output of
"pg_xlogdump -r MultiXact" for the WAL generated during the testing
period.
--
Álvaro Herrera http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services