On Wed, Jul 12, 2017 at 12:30 AM, Charles Nadeau <charles.nad...@gmail.com> wrote:
> > I use noop as the scheduler because it is better to let the RAID > controller re-arrange the IO operation before they reach the disk. Read > ahead is set to 128: > > charles@hpdl380g6:~$ cat /sys/block/sdc/queue/read_ahead_kb > 128 > charles@hpdl380g6:~$ cat /sys/block/sdc/queue/scheduler > [noop] deadline cfq > > > Perhaps pg_test_fsync ( https://www.postgresql.org/docs/9.6/static/pgtestfsync.html) and pg_test_timing will help shed some light here, or at the very least give some numbers to compare against.
