JPS61276039A - Processor using ratio measuring system - Google Patents

Abstract

PURPOSE:To obtain the processor using rate in measuring period time by reading the counting value of processor unusing time by a timer interruption for the measuring period, in a processor using rate measuring system. CONSTITUTION:A processor 1 comes to be holding (HALT) condition when an instruction to be processed is not executed, and generates a signal HALT. While the signal is sent through an AND circuit 5 to a counting circuit 2 together with the clock pulse and at the circuit 2, while an HALT signal is sent from the processor 1, namely, while the processor 1 is not used, at the constant interval, the peripheral using time of the processor is counted based upon the clock pulse. On the other hand, a timer circuit 3 gives the interruption to the processor 1 for one constant period, and at such a time, the counting value of the circuit 2 is read. By the rate of the counting value and the interrupting period of the timer circuit 3, the unusing rate of the processor is calculated, the numeric of the unusing rate is extracted from the processor 1, and the average using rate of the processor in one measuring period time is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for measuring the usage rate of a hardware processor, such as a CPU.

[Prior Art] Examples of conventional processor usage rate measurement methods include the following.

That is, when there is no processing to be performed by the processor, the program enters an infinite loop, and the counter counts the number of digits that go through the loop. This count value is read every measurement period by a timer included in the software, and is cleared after reading. The unused time of the CPU within the measurement cycle time can be obtained by multiplying the count value described above by the execution time for one round of the infinite loop. Further, by subtracting the unused time of the processor from the measurement cycle time, the used time of the processor can be obtained. Therefore, the usage rate of the processor can be obtained by determining the ratio of the usage time of the processor within the measurement cycle time.

[Problems to be Solved] In the conventional processor usage rate measuring method described above, the unused time of the processor is calculated from the number of times the program goes through an infinite loop. Therefore, if the processor's program execution speed changes due to changes in memory access speed, or if the program execution speed decreases due to the DMA device monopolizing the 7 hess, the number of times the program goes through an infinite loop will also change. Correct count values will no longer be obtained. Therefore, there is a problem in that the processor usage rate obtained based on the loop count value also has an error.

[Means for Solving the Problems] In order to solve the above problems, the processor usage rate measurement method according to the present invention has a method of measuring the processor usage rate based on the unused time of the processor, in which there are no instructions to be processed. A processor that sometimes enters a hold state, a counter circuit that counts the unused time of the processor at fixed time intervals when the processor is in a hold state, and a It has a timer circuit that always keeps the cycle constant for interrupts generated by the system, and reads the count value of unused time of the processor by the timer interrupt at each measurement cycle, and calculates the processor usage rate within the measurement cycle. It is something to seek.

[Example] Hereinafter, an example of the present invention will be described based on the drawings. 1st
FIG. 1 is a block diagram of a circuit for illustrating a processor usage rate measurement method according to an embodiment of the present invention.

As shown in the figure, when there is no instruction to be processed, the processor 1 enters a hold (HALT) state and issues a HALT signal. This HALT signal along with the clock pulse
The signal is sent to the count circuit 2 via the D circuit 5, and the count circuit 2 counts the unused time of the processor 1 at regular intervals while the HALT signal is sent from the processor 1, that is, while the processor 1 is in an unused state. is counted based on clock pulses.

On the other hand, the timer circuit 3 interrupts the processor 1 at regular intervals using a timer included in the software, and reads the count 1η of the count circuit 2 at this time. The unused bunch of processors is calculated by taking the ratio of this count value and the interrupt period of the timer circuit 3, and then the average usage rate of the processors within one measurement period is calculated by subtracting the above unused rate from l. get. Note that 4 in the figure is a data bus. Further, the count value is cleared in preparation for the next cycle of counting after the count value is read by a timer interrupt.

In this type of processor usage rate measurement method, even if the interrupt processor is processing other interrupts when a measurement period interrupt occurs and there is a delay in accepting the interrupt, the processor L is in a HALT state because it is processing other processes. Instead, the HALT state, that is, the unused time count value read when the other processing is completed and the 18th measurement period interrupt is accepted, remains the same as the value at the time the periodic interrupt occurred. Therefore, even if there is a delay in accepting the 411 periodic interrupt, no error will occur in the measured value.

[Effects of the Invention] As explained above, in the processor usage rate measurement method according to the present invention, the numerical error in calculating the processor unused time is extremely small, so that it is possible to obtain an accurate processor usage rate.

[Brief explanation of the drawing]

FIG. 1 is a circuit block diagram of an embodiment of a processor usage rate measuring method according to the present invention. 1: Processor 2: Count circuit 3: Timer circuit

Claims (1)

[Claims] In the method of measuring the processor usage rate based on the unused time of the processor, there is a processor that enters the hold state when there are no instructions to process, and a count of the unused time of the processor at fixed time intervals while the processor is in the hold state. and a timer circuit that always keeps the cycle constant for interrupts generated to the processor to read the count value of the count circuit, and the timer circuit keeps the cycle constant for interrupts generated to the processor to read the count value of the count circuit. A processor usage rate measuring method characterized by reading a count value of usage time and determining the processor usage rate within a measurement cycle time.