Everything worked fine a few days ago. I think everything worked perfectly fine till I tried to create an AMI of this EC2 instance. It appears that the creation attempt caused the server to become non-responsive, so I stopped that process and restarted the server. It's Windows Server 2008 R2, running 6 ASP sites and 6 PHP sites. All PHP sites identical, all ASP sites identical.
On some of the sites, they load fast and without incident. Some of them put W3WP to 100% and they just don't load, eventually throwing a 500 error and subsequent refreshes say the site is unavailable. (Sometimes - I just tried again and got no unavailable errors, but still got 500 after the server timed out)
None of this makes sense to me, they should all load the same and they shouldn't have been effected by any of this. Any ideas would be great!