Find out why the system process occupies 100% CPU.

1. run "perfmon" to open performance management. Right-click the right pane and select "Add counter". In the "performance object" drop-down menu, select "thread ", select example from the list, select all syetem threads (such as system/0 and system/NNN), and add them to the chart.
View the system instance corresponding to the thread with the highest CPU usage, and write down the instance number.

2. Use VC or Borland to check the thread tool to find the memory address of the instance, and then use pstat or another tool to check the name of the Library call that is close to the memory address, which is the root cause of the problem.