We had IIS 6 on Win 2003, we upgraded to Win 2008, and now our application is the same, basically its simple file server, which resizes images and caches them and delivers them to clients. Since resizing requires more memory, working under the Pipelined Pool causes more memory errors, so we returned to classic mode and there is no website, only one, and we are happy with it.
This morning I saw that the website was not working, and I went and checked the CPU usage on the server, it showed 100% w3wp.exe CPU usage, now we never had this problem, the code is the same that we used into old IIS 6 and its simple read and response Database.Write.
Restarting the server solved the problem, but if I get the same problem again, how can I check how much of the code on our site used such huge processor utilization, where there is absolutely no error log, as well as event view errors.
The code used on the website is a bit few lines, a typical DAL query for a database and response.write thats all. Files are stored in blocks in the database, but this does not mean anything, because it has been successfully running for 3 years with the same SQL Server. The only change is IIS 7 and its classic application pool with IIS 6 with the default application pool.
I would use any tool or, in any case, to control what caused this problem. We have Win 2008, launched from the last 30 days, and we received this error only once.