I wrote: > The fsync is associated with the write, which is not done with insert > lock held. We're not quite that dumb. But wait --- are you thinking of the call path where a write (and possible fsync) is forced during AdvanceXLInsertBuffer because there's no WAL buffer space left? If so, that's *exactly* the scenario that can be expected to be less common with more buffer space. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance