Monitoring and Analyzing Performance Using Performance Monitor

Introduced earlier, Performance Monitor provides a wide range of counters that you can add to the Performance Monitor graph and analyze visually. Performance Monitor, or PerfMon for short, will also dump measurements to a file for later analysis. The ASP.NET Apps Performance object provides a number of counters for monitoring requests , responses, and sessions for a specific application. If your Web server is running multiple Web applications, then you will need to select a specific application instance from an available list on the selection screen. Table 1-1 summarizes several of these counters.

Table 1-1: ASP.NET Apps Performance Counters
COUNTER	DESCRIPTION
Anonymous Requests	The number of requests utilizing anonymous authentication
Request Bytes In Total	The total size , in bytes, of all requests
Request Bytes Out Total	The total size, in bytes, of responses sent to a client, excluding the standard HTTP Response headers
Requests Executing	The number of requests currently executing
Requests Timed Out	The number of requests that timed out
Requests/Sec	The number of requests executed per second
Output Cache Entries	The current number of entries in the output cache
Cache API Entries	The total number of entries within the cache added by the user

Note that these counters are specifically for the ASP.NET Apps v1.0.3705.0 Performance object, where the version number refers to the .NET Framework. ASP.NET installs another Performance object called ASP.NET v1.0.3705.0, which contains counters for monitoring ASP.NET performance overall, instead of for a specific application. These counters are useful when your Web server is hosting multiple Web applications and you suspect that one Web application is adversely affecting the performance of another by taking up too many resources. Table 1-2 summarizes several of these counters.

Table 1-2: ASP.NET Performance Counters
COUNTER	DESCRIPTION
Applications Running	The number of currently running applications
Requests Queued	The number of requests waiting to be processed
State Server Sessions Active	The number of sessions currently active

As noted earlier, the ASP.NET counters are not the only ones that indicate the overall performance of the system. There are several Performance objects for the server, including the Processor object, which provides counters that monitor how hard the machine processor is working. Performance Monitor is an excellent tool for monitoring the performance and health of a server, as well as an application. It also allows you to save a collection of counters so you can consistently generate graphs and reports as needed.