I recently inherited a dinosaur Classic ASP site that has some fresh blood pumped in to it in the form of intertwined ASPNET MVC 2. I have duplicated the site on the same server (Windows 2008 R2, 4GB, quad core, vm) to setup a poor man's staging site. As we were trying to sort some legacy bugs in the Classic ASP admin module we noticed that the RAM usage would steadily go up from about 1.3GB (incl system usage and 3 other sites) to max out at 4GB over the course of about 3.5 minutes AND the CPU would be close to max on all cores ONLY WHEN WE TESTED WITH FIREFOX (latest 3.6.9 and 3.6.8 - we didn't have older versions lying around to test with). We tested the same pages with IE8, IE7 via compat mode, IE6 with IETester, IE7 with IETester, latest CHrome, latest Opera and latest Safari but all would behave normally. The live version of the site does not have this issue. FireFox runs very well, almost as well as Chrome, and much better than all versions of IE.
Has anybody come across anything like this before? Any ideas on hunting down the issue? I could probably nuke the staging site and try to set it up from scratch but I am intrigued how a particular browser could cause a server issue...
Cheers