Method and devices for controlling operations of a central processing unit
View Patent ↗Control circuitry controls the operations of a central processing unit, CPU, which is associated with a nominal clock frequency. The CPU is further coupled to an I/O range and configured to deliver input to an application. The control circuitry controls the CPU to poll the I/O range for input to the application. The control circuitry also monitors whether or not each poll results in input to the application and adjusts a clock frequency at which the CPU operates to a clock frequency lower than the nominal clock frequency if a pre-defined number of polls resulting in no input is detected. Methods and a central computer server of an automated exchange system are also provided.
1. A method for use in a system including control circuitry for controlling operations of a processor, wherein the processor is associated with an input/output (I/O) range, has a nominal clock frequency, and is configured to deliver input to an application, the method comprising:
at the control circuitry:
controlling the processor to perform one or more polls of the I/O range;
monitoring whether each of the polls is a positive poll or a negative poll, wherein a poll is a positive poll when it results in detection of input data for the application at the I/O range and is a negative poll when it does not result in the detection of input data for the application at the I/O range; and
in response to determining that a given number of the polls are negative polls, adjusting a clock frequency at which the processor operates to a first clock frequency that is lower than the nominal clock frequency.
2. The method of claim 1 , wherein the controlling the processor to perform the polls is performed in response to an instruction from the application.
3. The method of claim 1 , wherein the monitoring involves monitoring read operations on the I/O range, and a negative poll is detected by detecting, within a given number of instructions following a performed read operation on the I/O range, a return to the same instruction to read the I/O range.
4. The method of claim 1 , wherein the processor is a central processing unit (CPU).
5. The method of claim 1 , wherein the control circuitry is included within the processor.
6. The method of claim 1 , wherein the control circuitry is not included within the processor.
7. The method of claim 1 , wherein the I/O range is one of:
an I/O port; or
a memory address to which an I/O device is mapped.
8. A method for use in a system including a processor, wherein the processor has a nominal clock frequency, is associated with an input/output (I/O) range, and is configured to deliver input to an application, the method comprising:
at the processor:
performing one or more polls of the I/O range;
monitoring whether each of the polls is a positive poll or a negative poll, wherein a poll is a positive poll when it results in detection of input data for the application at the I/O range and is a negative poll when it does not result in the detection of input data for the application at the I/O range; and
in response to determining that a given number of the polls are negative polls, adjusting a clock frequency at which the processor operates to a first clock frequency that is lower than the nominal clock frequency.
9. The method of claim 8 , wherein the polls are performed in response to an instruction from the application.
10. The method of claim 8 , wherein the monitoring involves monitoring read operations on the I/O range.
11. The method of claim 10 , wherein a negative poll is detected by detecting, within a given number of instructions following a performed read operation on the I/O range, a return to the same instruction to read the I/O range.
12. The method of claim 8 , wherein the processor is a central processing unit (CPU).
13. The method of claim 8 , wherein the I/O range is an I/O port.
14. The method of claim 8 , wherein the I/O range is a memory address to which an I/O device is mapped.
15. The method of claim 8 , wherein the given number of the polls is one.
16. A computing device, comprising:
an input/output (I/O) range; and
a processor that has a nominal clock frequency, is coupled to the I/O range, and is configured to execute an application;
wherein the processor is configured to perform actions that include:
performing one or more polls of the I/O range;
monitoring whether each of the polls is a positive poll or a negative poll, wherein a poll is a positive poll when it results in input data for the application and is a negative poll when it does not result in input data for the application; and
in response to determining that a given number of the polls are negative polls, adjusting a clock frequency at which the processor operates to a first clock frequency that is lower than the nominal clock frequency.
17. The computing device of claim 16 , wherein the polls are performed in response to an instruction from the application.
18. The computing device of claim 16 , wherein the monitoring involves monitoring read operations on the I/O range.
19. The computing device of claim 16 , wherein the I/O range is an I/O port.
20. The computing device of claim 16 , wherein the I/O range is a memory address to which an I/O device is mapped.