When you open the Windows Task Manager and select the Processes tab and then select the “show processes from all users” button, you will find many instances of the svchost.exe as shown in the picture below.
So what are all these svchost.exe doing ? To get a detailed overview of each running svchost.exe you can run the follwing command at the command prompt that will list each svchost process its PID and the running services.
tasklist /svc /FI “IMAGENAME eq svchost.exe”
The SVCHOST Viewer, that can be downloaded from Codeplex provides you with even more details such as the memory used, the running services including a description of the service and the current service status.
of course you can also launch the sysinternals process explorer that can provide detailed svchost process informationn as well.