On Tue, Mar 27, 2012 at 5:06 PM, Joshua Berkus <josh@agliodbs.com> wrote:
> In an effort to test this, we deliberately ran a pg_dump. This did grow the cache to all available memory, but Linux
rapidlycleared the cache (flushing to disk) down to 25GB within an hour.
This would happen if some queries (or some program) briefly uses that
much memory (pushing the cache off RAM).