I've got a site that has recently been experiencing a lot of downtime due to max memory usage. We're running a VPS with 8GB RAM, Windows Server 2008 R2, IIS 7.5, WebForms 4.0 site with SQL Express running on the same server. Usually the RAM is well under 2GB usage. I caught it in action one time ramping up quickly to max the RAM, then suddenly drop.
We've changed a few things since then and have been ok for a few days, so maybe that issue is fixed. However, I also started logging information through Performance Counter. I found that the total requests in IIS was slowly ramping up, but then suddenly dropped. However, the ram didn't correspond to a slow increase. (The blue line is RAM, the purple line is Total Request.)
What would cause this request ramping up and how do I resolve it? App pool recycling? How do you limit the request length so they timeout, and is this the right approach?