Re: How clear the cache on postgresql?

On Fri, 2017-11-24 at 11:58 -0800, John R Pierce wrote:
> 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.

Given that a real-world application will almost never experience an
empty-cache scenario I question the usefulness of clearing the
cache(s).   I would capture transactions from a production database in
order to create a load test that mimics real-world load.

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