>If somebody produced a trace showing the buffer lookups in order To get things moving, I've created a DTrace script that captures buffer reads: https://github.com/vlsi/pgsqlstat/blob/pgsqlio/pgsqlio
Is it something that can be used to capture live traces? Sample output can be seen here: https://github.com/vlsi/pgsqlstat/tree/pgsqlio#pgsqlio For instance (time units are nano-seconds): Timestamp Elapsed ForkNum BlockNum TableSp DataBase Relation Cached 3271837060212 1563 0 1 1663 16385 1259 1 3271838881374 88205 0 0 1663 16385 16604 0 3271840973321 4368 0 0 1663 16385 16604 1 If DTrace is acceptable, trace format might be adjusted for easier consumption by https://github.com/ben-manes/caffeine/wiki/Simulator Vladimir
