SecureConnectGateway Lack of Available Memory and SAN Alarms

We have two SecureConnectGateways.    One for each of our SAN sites.   The SANs will communicate with each of the SecureConnectGateways and I believe they have been clustered on the back end.    Occasionally we will encounter an issue with one or the other where the Gateway runs out of available Memory for a span of time and the SANs will alert that their Gateway connection is Not_Connected.    I'm not sure if there is a monthly discovery or some other process involved but we've encountered the same problem on each of the Gateways in the time that we've had them online (3 months).    We are running the Virtual Edition - 5.10.0.10.      We have a very small environment, so I'm not sure why we're using 13GB at each site out of 16GB pretty much all of the time.    Is there a tuning option available to reduce the footprint?    Any recommendations, ideas.