Bruce Momjian <bruce(at)momjian(dot)us> writes:
> My guess is that having a very long fuzzy checkpoint time means that
> when you fsync you are fsync'ing lots of data, both your checkpoint data
> and other writes performed by backends.
Hmm, could be ... although that would imply that shared_buffers should
be kicked up some more, so the backends aren't doing so many writes for
themselves.
regards, tom lane