Apparatus and method for dynamically adjusting frequency of central processing unit

A method for dynamically adjusting a frequency of a CPU for a computer system which executes a CPU bound application and a memory bound application, the method comprising:

• acquiring a ratio of memory access instruction as executing an application task set;
• calculating an adjusted new frequency of the CPU in inverse proportion to the ratio of memory access instruction acquired;
• and
• adjusting the frequency of the CPU to a new frequency of the CPU,
• wherein the step of calculating the adjusted new frequency of the CPU in inverse proportion to the ratio of memory access instruction acquired comprises:
• employing a negative feedback mechanism to calculate the adjusted new frequency of the CPU by the following expression:
• fnew=fnow+p1*(−m),
• where fnow is a current frequency of the CPU, fnew is the adjusted new frequency of the CPU, m is the ratio of memory access instruction, and p1 is a control parameter.

A computer system for executing a CPU bound application and a memory bound application, which comprises:

• a controller for acquiring a ratio of memory access instruction as executing an application task set, calculating an adjusted new frequency of the CPU in inverse proportion to the ratio of memory access instruction acquired, and adjusting the frequency of the CPU to a new frequency of CPU,
• wherein calculating the adjusted new frequency of the CPU in inverse proportion to the ratio of memory access instruction acquired comprises:
• employing a negative feedback mechanism to calculate the adjusted new frequency of the CPU by the following expression:
• fnew=fnow+p1*(−m),
• where fnowis a current frequency of the CPU, fnew is the adjusted new frequency of the CPU, m is the ratio of memory access instruction, and p1 is a control parameter.