On 11/24/2017 11:43 AM, Michael Nolan wrote:
There are so many different levels of caching going on--within Postgresql, within the OS, within a disk array or SAN, and at the individual drive--that there may no longer be a meaningful way to perform this measurement.
generally, power cycling the server will flush all the hardware caches AND the OS cache.
-- john r pierce, recycling bits in santa cruz
