JP2009026199A - Clock frequency control method and computer program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clock frequency control method and a computer program that can appropriately change the clock frequency of a processing unit in accordance with the number, scale or computational complexity of application programs executed. <P>SOLUTION: Correspondences between a plurality of application programs APs executable by a CPU 1 and required throughputs are stored in advance in an application table AT, and correspondences between total required throughputs and clock frequencies are stored in advance in a clock frequency table CT. When executing a plurality of application programs APs, a control program CP acquires and adds the required throughput of each application program AP from the application table AT to calculate the total required throughput, then determines the clock frequency on the clock frequency table CT, and changes the clock frequency accordingly. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a clock frequency control method and a computer program for changing a clock frequency of a processing device in accordance with the number, scale, or amount of calculation of application programs to be executed.

  In recent electric devices, a processing device such as a CPU (Central Processing Unit) or MPU (Micro Processing Unit) is mounted, and various application programs are executed. In addition, with the increase in performance of electrical equipment, the number of application programs that are simultaneously executed by one processing apparatus is increasing. The higher the application program to be executed and the more programs to be executed simultaneously, the higher the processing capacity of the processing device is required. As a method of increasing the processing capability of the processing device, there is a method of increasing the amount of calculation per unit time by increasing the frequency of the clock supplied to the processing device.

  However, there is a problem that the power consumption of the processing device increases by increasing the clock frequency of the processing device. For example, even if the processing device clock frequency is set high so that a plurality of advanced application programs can be executed simultaneously, the processing device does not always execute a plurality of advanced application programs simultaneously. Depending on the situation, only one simple application program may be executed. In such a case, the processing capability of the processing apparatus may be increased more than necessary, and power may be consumed more than necessary. For this reason, it is required that the processing frequency be changed with the optimum processing capacity by changing the clock frequency according to the scale and the number of executions of the application program.

In Patent Document 1, a CPU and a frequency synthesizer that supplies a clock signal having a variable clock frequency to another system bus based on an interrupt or application to be executed, a predetermined application to be executed, or use of the CPU Devices have been proposed for automatic CPU speed control that can change the clock frequency based on the degree or the like. In one embodiment of this apparatus, the clock frequency can be changed to the low speed mode or the high speed mode depending on whether or not the CPU is executing an idle task, and the clock frequency can be changed depending on the presence or absence of an interrupt. it can. In another embodiment, the CPU usage level can be dynamically monitored, and the clock frequency can be changed according to the CPU usage level. In yet another embodiment, an optimal clock frequency is predetermined and stored in a table for each application such as a word processor or voice dictation, and is changed to the optimal clock frequency stored in the table when the application is executed. Can do.
JP 2002-533801 A

  However, the apparatus for automatic CPU speed control described in Patent Document 1 determines whether or not an application is executed when the clock frequency is changed to the low speed mode or the high speed mode according to whether or not the idle task is executed. Only the clock frequency is changed, and even if it is a simple application or an advanced application, it is executed in the high-speed mode. Therefore, the above problem cannot be solved.

  Further, in the case of a configuration in which the clock frequency is changed according to the monitored CPU usage level, the clock frequency can be finely changed according to the CPU usage level, so that the above problem can be solved. However, there is a problem that excessive CPU resources are consumed. For this reason, this configuration can be realized by a high-grade system such as a PC (personal computer) or WS (workstation), but this configuration can be realized by a small microcomputer mounted on an electrical device. It's not easy.

  In addition, when the optimal clock frequency is stored in a table for each application and the application is changed to the optimal clock frequency stored in the table when the application is executed, the optimal clock frequency is set according to the scale of the application. Can be changed. However, when a plurality of applications are operated simultaneously, there is a problem that the clock frequency cannot be changed to the optimum. For example, the optimum clock frequency for each application can be compared and changed to the maximum clock frequency. However, when many simple applications are operated, there is a possibility that sufficient processing capability may not be obtained.

  In this configuration, the clock frequency for each application stored in the table in advance is a value specific to the hardware determined according to the configuration and performance of the CPU, so the same application is executed by a CPU with a different configuration. In this case, a new table must be created by newly calculating a clock frequency optimum for another CPU for each application, and there is a problem that versatility is low.

  The present invention has been made in view of such circumstances, and an object of the present invention is to store in advance correspondence between a plurality of application programs and necessary processing capacity required for execution, and execute the programs simultaneously. Optimal even when multiple application programs are executed by calculating the total required processing capacity based on each required processing capacity of the application program and determining and changing the clock frequency according to this total required processing capacity Another object of the present invention is to provide a clock frequency control method and a computer program that can operate a processing device (computer) at a different clock frequency.

  Another object of the present invention is to previously store the correspondence between the total required processing capacity and the clock frequency, and calculate the total required processing capacity calculated based on each required processing capacity of the application program to be executed simultaneously. By acquiring the clock frequency corresponding to the above, it is not necessary to store the clock frequency for each application, and a highly versatile clock frequency control method is provided.

  Another object of the present invention is to execute a first control program on a processing device, execute a second control program on the first control program, and execute an application program on the second control program. , And the second control program calculates the total required processing capacity based on the correspondence between the application program and the required processing capacity. It is to provide a method.

  Another object of the present invention is when the application program to be executed is added by the second control program generating a correspondence between the application program and the necessary processing capacity in accordance with the application program to be executed. Another object of the present invention is to provide a clock frequency control method capable of automatically generating a correspondence by a second control program.

  Further, another object of the present invention is that the second control program determines and changes the clock frequency of the processing device based on the correspondence between the total required processing capacity and the clock frequency. An object of the present invention is to provide a highly versatile clock frequency control method that can easily cope with a change.

  Another object of the present invention is that the second control program generates a correspondence between the total required processing capacity and the clock frequency in accordance with the scale, processing capacity and configuration of the processing apparatus. Another object of the present invention is to provide a clock frequency control method capable of automatically generating a response by the second control program when the configuration of the processing device is changed.

  A clock frequency control method according to a first aspect of the present invention is a clock frequency control method for controlling a change in clock frequency of a processing device that executes a plurality of application programs. And calculating the total required processing capacity required for executing the one or more application programs based on each required processing capacity of the one or more application programs executed by the processing device, The clock frequency is determined according to the calculated total required processing capacity, and the clock frequency of the processing device is changed to the determined clock frequency.

  The clock frequency control method according to the second aspect of the present invention stores the correspondence between the total required processing capacity and the clock frequency, acquires the corresponding clock frequency based on the calculated total required processing capacity, and changes the clock. The frequency is determined.

  The clock frequency control method according to a third aspect of the present invention is the first frequency control program according to the configuration of the processing device and the second control program for executing the application program, wherein the processing device uses the first control program. 1 control program, execute the second control program on the first control program, execute the application program on the second control program, and in the second control program, The total required processing capacity is calculated based on the correspondence between the application program and the required processing capacity.

  According to a fourth aspect of the present invention, there is provided a clock frequency control method for generating a correspondence between an application program and a required processing capacity in the second control program in accordance with an application program executed in the processing device. And

  The clock frequency control method according to the fifth invention is characterized in that the second control program determines the clock frequency to be changed based on the correspondence between the total required processing capacity and the clock frequency.

  According to a sixth aspect of the present invention, there is provided a clock frequency control method for generating a correspondence between a total required processing capacity and a clock frequency in the second control program in accordance with a processing device that executes an application program. To do.

  According to a seventh aspect of the present invention, there is provided a computer program for causing a computer to control the change of the clock frequency because of correspondence between a plurality of application programs stored in advance in the computer and the necessary processing capability required to execute each application program. , Obtaining each necessary processing capability of one or a plurality of application programs to be executed by the computer, and calculating a total necessary processing capability required for executing the one or a plurality of application programs based on the obtained each necessary processing capability The clock frequency is determined in accordance with the calculated total required processing capacity, and the clock frequency of the computer is changed to the determined clock frequency.

In the present invention, the correspondence between a plurality of application programs executed by the processing device and the necessary processing capacity required for execution is stored in advance as a table, for example. The application program is stored even when the configuration of the processing device is changed by storing, for each application program, the necessary processing capacity not related to the configuration of the processing device, instead of the clock frequency determined by the configuration of the processing device. There is no need to change the correspondence between and the required processing capacity. Even when an application program to be executed is added, it is only necessary to add the necessary processing capability for this application program.
When changing the clock frequency of the processing device, the total required processing capacity is calculated based on the respective required processing capacity of the application program to be executed simultaneously, and the clock frequency is determined according to the total required processing capacity. For example, when the required capacity of each application program is set as a numerical value, the total required processing capacity may be calculated by simple four arithmetic operations such as addition. Since the clock frequency is determined not for each application program but for the total required processing capacity, the determination method does not need to be changed by adding an application program to be executed. When changing the clock frequency, it is possible to determine the clock frequency to be changed by a simple calculation by examining the correspondence stored in advance, so that it does not consume excessive resources of the processing device, and even a small processing device The clock frequency can be changed by this method.

  In the present invention, the correspondence between the total required processing capacity and the clock frequency is stored in advance as a table, for example. Since only the clock frequency for the total required processing capacity is stored, not for each application program, it is not necessary to change the correspondence even when an application program to be executed is added.

  In the present invention, the processing device executes the first control program, executes the second control program on the first control program, and executes the application program on the second control program. Since the execution of the program has a hierarchical structure, for example, when the configuration of the processing device is changed, only the first control program needs to be changed. Further, when the second control program calculates the total required processing capacity based on the correspondence between the application program and the required processing capacity, when the application program to be executed is added, the configuration of the processing apparatus is increased. The correspondence between the application program and the necessary processing capacity may be added in the second control program that has no relation, and it does not affect the first control program, so the versatility is high.

  In the present invention, when an application program to be executed is added, the second control program generates a correspondence between the application program and the necessary processing capacity. For example, when information such as necessary processing capacity or calculation amount is stored as data in an application program in advance and the application program is added to the processing device, the second control program is added. Data can be read out from the application program, and the correspondence between the application program stored as a table and the necessary processing capacity can be added or corrected.

  In the present invention, the second control program determines the clock frequency of the processing device based on the correspondence between the total required processing capacity and the clock frequency. Since the first control program does not need to have a function of determining the clock frequency, the first control program can be easily changed when the configuration of the processing device is changed. The second control program only needs to change the correspondence between the total required processing capacity and the clock frequency.

  In the present invention, when the configuration of the processing apparatus is changed, the second control program generates a correspondence between the total required processing capacity and the clock frequency. For example, the second control program needs to be stored as a table or the like by acquiring information such as the scale and processing capacity of the processing device directly from the processing device or indirectly from the first control program. The correspondence between processing capability and clock frequency can be modified or changed.

  In the case of the first invention and the seventh invention, the correspondence between the application program and the required processing capacity is stored in advance, and the total required processing capacity is calculated based on each required processing capacity of the application program to be executed simultaneously, By determining and changing the clock frequency according to the total required processing capacity, it is possible to operate the processing device at the optimum clock frequency even when a plurality of application programs are executed. Even so, the clock frequency can be changed by this method. In addition, by storing the required processing capacity unrelated to the configuration of the processing apparatus for each application program, it is necessary to change the correspondence between the application program and the required processing capacity even when the configuration of the processing apparatus is changed. Because there is no, versatility is high. Therefore, by using the clock frequency control method and the control program of the present invention, the application program can be executed with sufficient processing capacity regardless of the configuration of the processing device or the configuration of the application program, and the processing by changing the clock frequency. It is possible to sufficiently reduce the power consumption of the apparatus.

  Further, in the case of the second invention, the correspondence between the total required processing capacity and the clock frequency is stored in advance, and the total required processing capacity corresponding to the total required processing capacity calculated based on each required processing capacity of the application program to be executed simultaneously is supported. By acquiring the clock frequency, it is not necessary to store the clock frequency for each application, and even if an application program to be executed is added, there is no need to change the stored correspondence, so a highly versatile clock A frequency control method can be realized.

  In the case of the third invention, the processing device executes the first control program, executes the second control program on the first control program, and executes the application program on the second control program. When the second control program calculates the total required processing capacity based on the correspondence between the application program and the required processing capacity, for example, when the configuration of the processing apparatus is changed, only the first control program is changed. In many cases, since it is possible to easily cope with addition of an application to be executed, a more versatile clock frequency control method can be realized.

  Further, in the case of the fourth invention, the second control program generates a correspondence between the application program and the required processing capacity in accordance with the application program to be executed, so that the application program is added to the processing device and added. In this case, since the second control program automatically generates the correspondence between the application program and the necessary processing capacity, it is not necessary to separately change the correspondence between the application program and the necessary processing capacity, and the clock is highly convenient. A frequency control method can be realized.

  Further, in the case of the fifth invention, the configuration of the processing device is changed by the second control program determining and changing the clock frequency of the processing device based on the correspondence between the total required processing capacity and the clock frequency. In this case, the first control program can be easily changed, and the second control program only needs to change the correspondence between the total required processing capacity and the clock frequency, and therefore can easily cope with the change in the configuration of the processing apparatus. Therefore, a more versatile clock frequency control method can be realized.

  According to the sixth aspect of the invention, the second control program generates a correspondence between the total required processing capacity and the clock frequency in accordance with the scale, processing capacity, configuration, etc. of the processing apparatus. When the configuration is changed, the second control program automatically generates the correspondence between the total required processing capacity and the clock frequency, so there is no need to separately change the correspondence between the total required processing capacity and the clock frequency. A more convenient clock frequency control method can be realized.

(Embodiment 1)
Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof. FIG. 1 is a block diagram showing a configuration example of a computer system to which a clock frequency control method according to the present invention is applied. In the figure, reference numeral 1 denotes a CPU that forms the core of a computer system, and is a processing device that performs various processes by executing various programs such as a control program and an application program. The illustrated computer system includes a main storage unit 2, an input unit 3, an output unit 4, an auxiliary storage unit 5 and the like connected to the CPU 1 via a bus, and a clock signal supplied to the CPU 1 and other units. (However, in FIG. 1, only the clock signal supply path from the clock generation section 6 to the CPU 1 is shown, and the clock signal supply path to the other sections is omitted.) )

  The main storage unit 2 is composed of a memory element that can be rewritten and accessed at high speed, such as SRAM (Static Random Access Memory) or DRAM (Dynamic Random Access Memory). It is used for the purpose of loading data or the like and accessing the CPU 1 or temporarily storing data generated in the course of the arithmetic processing of the CPU 1.

  The input unit 3 receives data input from the outside. For example, the input unit 3 includes a keyboard and a mouse, and receives data input from the user and notifies the CPU 1 of the data input. Further, for example, in the case of a small-scale electric device or the like, the input unit 3 is configured by a plurality of buttons and switches, a touch panel, or the like, and accepts data input from the user. Further, in the case of a control device or the like, the input unit 3 may be configured to receive detection results from various sensors as data input instead of receiving data input from the user.

  The output unit 4 outputs data to the outside. The output unit 4 includes a display device such as a liquid crystal display, and displays and outputs characters, photographs, pictures, and the like in accordance with a display command from the CPU 1. Further, for example, the output unit 4 may be configured by a printing apparatus such as a laser printer or an ink jet printer that prints out characters, photos, pictures, or the like. Further, in the case of a control device or the like, it may be configured to output a control signal to a device to be controlled.

  The auxiliary storage unit 5 includes a magnetic disk device such as a hard disk or a non-volatile memory element such as a flash memory. In addition, the auxiliary storage unit 5 may be configured by a storage medium such as a memory card, an optical disk, or a magnetic disk, and a drive device that loads these storage media and reads / writes data. In the auxiliary storage unit 5, various programs such as a control program CP and an application program AP executed by the CPU 1, and various data used when executing these programs are installed and stored in advance. It is. In the computer system to which the clock frequency control method according to the present invention is applied, the application table AT and the clock frequency table CT are stored as data in the auxiliary storage unit 5. Although details of these tables will be described later, the application table AT is a table for storing necessary processing capabilities for each application program AP executed by the CPU 1, and the clock frequency table CT is a clock generated by the clock generator 6. It is a table for determining the clock frequency of a signal.

  The clock generator 6 is a solid-state oscillator using a crystal oscillator or a ceramic oscillator, or an oscillation circuit that outputs an oscillation signal of a predetermined frequency, such as a ring oscillator, and an oscillation signal from the oscillation circuit. And a frequency dividing circuit for dividing and outputting. The clock generator 6 of this system can change the clock frequency of the clock signal to be output in accordance with an instruction given from the CPU 1. The clock frequency can be changed, for example, by changing the frequency division number of the oscillation signal by the frequency divider circuit described above.

  FIG. 2 is a schematic diagram for explaining a hierarchical structure of a program executed by the CPU 1. The program is executed by reading the control program CP, application program AP, and the like stored in the auxiliary storage unit 5 into the main storage unit 2, and the CPU 1 reading out the program code from the main storage unit 2. The programs executed by the CPU 1 can be roughly classified into two layers: a control program CP executed on the CPU 1 and an application layer by a plurality of application programs AP1 to AP3 executed on the control program CP. . The control program CP is a program such as an OS (Operating System) or an interpreter, for example, and the control program CP of the present invention includes an abstraction layer control program (first control program) executed on the CPU 1; It can be classified into two layers: a platform layer control program (second control program) executed on the abstraction layer control program.

  The abstraction layer control program abstracts the hardware configuration to the upper layer program and provides a common operating environment even when the lower-layer CPU 1 and other hardware configurations (architectures) are different. It is a program for. For this reason, the abstraction layer control program depends particularly on the hardware configuration of the CPU 1, and different abstraction layer control programs are used for different CPUs 1.

  The control program of the platform layer is a program that performs processing such as scheduling and resource management of the plurality of application programs AP1 to AP3 executed in the upper application layer. Further, since the platform layer control program is executed on the abstraction layer control program, the same platform layer control program can be used for different CPUs 1 without depending on the hardware configuration of the CPU 1. Furthermore, the platform layer control program of the present invention performs a process of changing the clock frequency of the clock signal generated by the clock generator 6 using the application table AT and the clock frequency table CT described above.

  The application programs AP1 to AP3 are, for example, word processors, spreadsheets, image editing programs, etc. when the system is a PC or WS. When the system is a control system that controls equipment mounted on a vehicle or the like, for example, door locking / unlocking, headlight or room lamp lighting / extinguishing control, or car navigation device or audio device It is a program that performs operation control and the like. A plurality of these application programs AP1 to AP3 can be executed simultaneously on the control program of the platform layer.

  FIG. 3 is a schematic diagram illustrating an example of the application table AT and the clock frequency table CT. The application table AT and the clock frequency table CT are stored in the auxiliary storage unit 5 in advance, and after being read out to the main storage unit 2, the platform layer control program changes the clock frequency. The application table AT is associated with the required processing capacity obtained by quantifying the required processing capacity for each of the application programs AP1 to AP3 that can be executed by the CPU 1, that is, the application programs AP1 to AP3 installed in the auxiliary storage unit 5. It is stored (see FIG. 3 (a)). In the illustrated example, the required processing capacity of the application program AP1 is 1, the required processing capacity of the application program AP2 is 10, and the required processing capacity of the application program AP3 is 20, so that the application program AP3 has the most advanced processing capability. Can be determined.

  The application table AT may be prepared in advance by the computer system designer shown in FIG. 1 and stored in the auxiliary storage unit 5, and the designers of the application programs AP1 to AP3 set the necessary processing capacity respectively. Then, it may be configured such that each application program is given as data, and the control program of the platform layer reads this data and automatically creates the application table AT.

  The clock frequency table CT stores a total required processing capacity that is a total value of required processing capacities of a plurality of application programs AP1 to AP3 that are executed at the same time, and an optimum clock frequency corresponding to this value. (See FIG. 3B). In this embodiment, the total required processing capacity is a value obtained by simply adding the required processing capacities of the application programs AP1 to AP3 of the application table AT (for example, the total is required when three application programs AP1 to AP3 are executed simultaneously). The required processing capacity is 1 + 10 + 20 = 31, and when the two application programs AP1 and AP2 are executed simultaneously, the total required processing capacity is 1 + 10 = 11). The program AP1 to AP3 may be configured to calculate the total required processing capacity by multiplying the necessary weights and the counts for weighting the programs AP1 to AP3, or may be calculated by other methods.

  Further, the clock frequency stored in the clock frequency table CT depends on the configuration of the CPU 1, the clock generator 6, and the like. The illustrated example is a case where the clock generator 6 can change the frequency of the clock signal in three stages of “low speed”, “medium speed”, and “high speed”, and the total required processing capacity is 1 to 10 When the total required processing capacity is 11 to 20, the clock frequency is set to “medium speed”, and when the total required processing capacity is 21 or more, the clock frequency is set to “high speed”. It is supposed to be set. The clock frequency table CT may be created in advance by the computer system designer or the CPU 1 designer and stored in the auxiliary storage unit 5, and the platform layer control program is stored in the CPU 1 or the abstraction layer. The clock frequency table CT may be automatically created by acquiring information related to the processing capability of the CPU 1 from a control program or the like.

  FIG. 4 is a timing chart showing an example of the execution of the application programs AP1 to AP3 and the change of the clock frequency. For example, when the application programs AP1 and AP2 are simultaneously executed by the CPU 1 at the time t0, the platform layer control program first requires the required processing capability “1” of the application program AP1 and the required processing of the application program AP2 from the application table AT. Capability “10” is acquired and added to calculate the total required processing capability “11”. Next, the platform layer control program obtains the clock frequency “medium speed” corresponding to the total required processing capacity “11” from the clock frequency table CT, so that the frequency of the clock signal output from the clock generator 6 is set to “medium speed”. Change to "".

  Further, when the application program AP3 is further executed simultaneously at time t1, the platform layer control program calculates the total required processing capacity “31” based on the application table AT, and the clock frequency “high speed” from the clock frequency table CT. In order to acquire “,” the frequency of the clock signal output from the clock generator 6 is changed to “high speed”. Hereinafter, the platform layer control program repeats the same processing, for example, during the period when only the application program AP1 is executed (t3 to t4, t5 to t6, t7 to t8), the clock frequency is set to "low speed" During the period in which the programs AP1 and AP2 are executed simultaneously (t0 to t1, t2 to t3, t4 to t5, t8 to t9), the clock frequency is set to “medium speed”, and the application programs AP1 and AP3 are simultaneously executed. The clock frequency is set to “high speed” during the period (t6 to t7) in which the application programs AP1 to AP3 are executed simultaneously (t1 to t2).

  FIG. 5 is a flowchart showing the procedure of the clock frequency changing process performed by the platform layer control program. In the clock frequency changing process, the platform layer control program checks whether or not the execution number of the application program AP executed by the CPU 1 has changed (step S1). If the execution number has not changed (S1: NO), wait until the number of executions changes. When there is a change in the number of executions of the application program AP (S1: YES), the platform layer control program reads the application table AT from the auxiliary storage unit 5 or the main storage unit 2 (step S2) and executes the application AP to be executed. The necessary processing capacity is acquired from the application table AT (step S3).

  Next, the platform layer control program calculates the total required processing capacity by adding the acquired required processing capacities (step S4), and reads the clock frequency table CT from the auxiliary storage unit 5 or the main storage unit 2 ( In step S5), the clock frequency to be changed is determined by acquiring the clock frequency corresponding to the calculated total required processing capacity from the clock frequency table CT (step S6). Thereafter, the platform layer control program changes the frequency of the clock signal output from the clock generator 6 to the determined clock frequency (step S7), and ends the process.

  In the computer system to which the clock frequency control method having the above configuration is applied, the correspondence between the application program AP and the required processing capacity is stored in the application table AT in advance, and the correspondence between the total required processing capacity and the clock frequency is previously stored. By storing in the clock frequency table CT, the control program of the platform layer can calculate the total required processing capacity by a simple calculation and determine the clock frequency of the CPU 1, so that the CPU 1 is a small or inexpensive CPU 1. However, the clock frequency changing process does not become a heavy load. Therefore, even in a system that executes a large number of application programs AP at the same time, the CPU 1 can perform processing at an appropriate clock frequency, and realize sufficient processing capability and sufficient low power consumption. Can do.

  In addition, the control program CP is divided into two layers: a platform layer control program and an abstraction layer control program, calculation of the total required processing capacity using the application table AT, determination of the clock frequency using the clock frequency table CT, etc. In the configuration in which the control program of the platform layer performs the above process, when the CPU 1 and other hardware configurations are changed, only the control program of the abstraction layer needs to be changed, and the control program of the platform layer is changed. Since it is not necessary, the versatility of the control program CP can be improved.

  The application table AT stores the necessary processing capacity unrelated to the CPU 1 and other hardware configurations in association with each application, so that the configuration of the CPU 1 and other hardware is changed. However, it is not necessary to change the application table AT, and the versatility is high. The clock frequency table CT stores the correspondence between the total required processing capacity and the clock frequency, and it is not necessary to store the clock frequency for each application program AP, so a new application program AP is installed. Even in this case, it is not necessary to change the clock frequency table CT, and the versatility is high. Therefore, the clock frequency control method of the present invention is highly versatile and can be applied to various systems, and the application program AP with sufficient processing capability regardless of the configuration of the CPU 1 and other hardware or application program AP. The power consumption of the processing apparatus can be sufficiently reduced by changing the clock frequency.

  In the present embodiment, the three application programs AP1 to AP3 are executed by the CPU 1. However, the present invention is not limited to this, and two or less or four or more application programs AP are executed simultaneously. It is good also as composition to do. Further, the values shown in the application table AT and the clock frequency table CT in FIG. 3 are examples and are not limited thereto. Similarly, the timing chart shown in FIG. 4 is an example and is not limited thereto. Furthermore, the computer system shown in FIG. 1 is an example, and the present invention is not limited to this. The present invention can be applied to various systems.

(Embodiment 2)
The clock frequency control method according to the second embodiment is obtained by adding a method for automatically generating the application table AT to the clock frequency control method according to the first embodiment. FIG. 6 is a schematic diagram showing a configuration in which a new application program AP4 is added to the hierarchical structure shown in FIG. The application program AP4 is added by installing the application program AP4 in the auxiliary storage unit 5 of the computer system shown in FIG. Accordingly, since the application program AP4 is added to the application layer, the platform layer control program needs to change the application table AT. There is no need to change the clock frequency table CT.

  FIG. 7 is a schematic diagram showing an example of the changed application table AT. Items related to the added application program AP4 are added to the application table AT shown in FIG. In the illustrated example, the necessary processing capability of the application program AP4 is “10”. The application table AT is changed by the platform layer control program, but the application program AP1 to AP4 is pre-assigned data related to the required processing capability so that the platform layer control program can acquire the required processing capability. It is. This data may be given in advance by the designer of each of the application programs AP1 to AP4, for example. Therefore, when a new application program AP4 is installed, the platform layer control program can acquire data related to the required processing capacity from the application program AP4 and change the application table AT.

  FIG. 8 is a timing chart showing an example of execution of the application programs AP1 to AP4 and change of the clock frequency. In the illustrated example, the clock frequency is set to “low speed” during the period (t3 to t4, t6 to t7, t8 to t9) in which only the application program AP1 is executed. Periods (t0 to t1, t2 to t3, t5 to t6, t10 to t11) in which the application programs AP1 and AP2 are executed simultaneously and periods (t4 to t5) in which the application programs AP1 and AP4 are executed simultaneously are The clock frequency is set to “medium speed”. A period (t7 to t8) in which the application programs AP1 and AP3 are executed simultaneously, a period (t1 to t2) in which the application programs AP1 to AP3 are executed simultaneously, and the application programs AP1, AP2, and AP4 are simultaneously executed. During the execution period (t9 to t10), the clock frequency is set to “high speed”. As described above, even when the application program AP3 is not executed due to the addition of the application program AP4, the clock frequency is "high speed" if the three application programs AP1, AP2, and AP4 are executed. Set to

  FIG. 9 is a flowchart showing a procedure for creating the application table AT performed by the platform layer control program. In the process of creating the application table AT, the platform layer control program checks whether or not the application program AP is newly installed in the auxiliary storage unit 5 (step S21), and if it is not installed (S21: NO). Wait until a new application program AP is installed.

  When a new application program AP is installed (S21: YES), the platform layer control program acquires the necessary processing capacity from the installed application program AP (step S22), and obtains the application table AT from the auxiliary storage unit 5. Reading (step S23), the necessary processing capability for the installed application program AP is added, and the application table AT is updated (step S24). Thereafter, the control program for the platform layer overwrites and saves the updated application table AT in the auxiliary storage unit 5 (step S25), and ends the creation process of the application table AT.

  In the computer system to which the clock frequency control method of the second embodiment is applied, when the application program is installed in the auxiliary storage unit 5 and added, the platform layer control program automatically changes the application table AT. Therefore, it is not necessary for a user who uses the computer system to change the application table AT. Therefore, the convenience of the computer system can be improved.

(Embodiment 3)
The clock frequency control method according to the third embodiment is obtained by adding a method for automatically generating the clock frequency table CT to the clock frequency control method according to the first embodiment. FIG. 10 is a schematic diagram showing a configuration in which the CPU 1 is changed to a new CPU 1a in the hierarchical structure shown in FIG. 2, wherein (a) shows the configuration before the change, and (b) shows the configuration after the change. is there. For example, when the CPU 1 of the computer system is changed for the purpose of upgrading the CPU 1 or the like, it is necessary to change the control program of the abstraction layer and the clock frequency table CT depending on the configuration of the CPU 1 to be suitable for the new CPU 1a. There is no need to change the platform layer control program and application table AT independent of the configuration of the CPU 1.

  FIG. 11 is a schematic diagram showing an example of the changed clock frequency table CT. (A) shows the clock frequency table CT before the change, and (b) shows the clock frequency table CT after the change. In the illustrated example, when the CPU 1 is upgraded to the CPU 1a, the processing capacity is increased. When the total required processing capacity is 1 to 20, the clock frequency is set to "low speed" and the total required processing capacity is 21 to 40. When the clock frequency is set to “medium speed” and the total required processing capacity is 41 or more, the clock frequency is set to “high speed”.

  The change of the clock frequency table CT is performed by the platform layer control program. The platform layer control program acquires information on the processing capability of the CPU 1a from the CPU 1a or the changed abstraction layer control program. The information on the processing capacity is, for example, information such as the amount of data that the CPU 1a can process per clock, the number of instructions that can be processed in parallel, or the number of pipelines when the CPU 1a performs pipeline processing. The layer control program can determine the processing capability of the CPU 1a based on these pieces of information, and can determine the correspondence between the total required processing capability and the clock frequency. Information regarding these processing capabilities may be stored in the CPU 1a in advance so that the designer of the CPU 1a can directly acquire the information from the CPU 1a, or may be stored in an abstraction layer control program for the CPU 1a. May be.

  FIG. 12 is a timing chart showing an example of execution of the application programs AP1 to AP3 and change of the clock frequency when the changed clock frequency table CT is used. In the illustrated example, a period in which only the application program AP1 is executed (t3 to t4, t5 to t6, t7 to t8), and a period in which the application programs AP1 and AP2 are executed simultaneously (t0 to t1, t2 to t3). , T4 to t5, t8 to t9), the clock frequency is set to "low speed". The clock frequency is set to “medium speed” during the period (t1 to t2) when the application programs AP1 to AP3 are executed simultaneously and the period (t6 to t7) when the application programs AP1 and AP3 are executed simultaneously. The Also, the clock frequency is never set to “high speed”. This indicates that since the CPU 1a has a sufficiently high processing capability, the clock frequency is sufficient at “medium speed” and more application programs AP can be executed simultaneously.

  FIG. 13 is a flowchart showing the procedure of the process of creating the clock frequency table CT performed by the platform layer control program. In the process of creating the clock frequency table CT, the platform layer control program first checks whether the CPU 1 of the computer system has been changed (step S41). For example, when the control program for the platform layer is executed for the first time after the computer system is turned on, the version information of the control program for the CPU 1 or the abstraction layer is checked. So that you can know. When the CPU 1 has not been changed (S41: NO), it is not necessary to create the clock frequency table CT, so the platform layer control program ends the process of creating the clock frequency table CT.

  When the CPU 1 is changed (S41: YES), the platform layer control program acquires information on the processing capability of the CPU 1 from the CPU 1 or the abstraction layer control program (step S42), and the clock frequency is based on the acquired information. A table CT is created (step S43). Next, the platform layer control program overwrites and saves the created clock frequency table CT in the auxiliary storage unit 5 (step S44), and ends the process of creating the clock frequency table CT.

  In the computer system to which the clock frequency control method of the third embodiment is applied, the computer system is used because the control program of the platform layer automatically changes the clock frequency table CT when the CPU 1 is changed. There is no need for the user or the like to change the clock frequency table CT. Therefore, the convenience of the computer system can be improved. In the present embodiment, the clock frequency table CT is changed when the CPU 1 is changed. However, the present invention is not limited to this. For example, the clock generator 6 can change the clock frequency in four stages. The clock frequency table CT may also be changed when the configuration of other hardware is changed, such as when the hardware is upgraded.

It is a block diagram which shows one structural example of the computer system to which the clock frequency control method which concerns on this invention is applied. It is a schematic diagram for demonstrating the hierarchical structure of the program run by CPU. It is a schematic diagram which shows an example of an application table and a clock frequency table. It is a timing chart which shows an example of execution of an application program, and change of a clock frequency. It is a flowchart which shows the procedure of the clock frequency change process which the control program of a platform layer performs. It is a schematic diagram which shows the structure which added the new application program in the hierarchical structure shown in FIG. It is a schematic diagram which shows an example of the changed application table. It is a timing chart which shows an example of execution of an application program, and change of a clock frequency. It is a flowchart which shows the procedure of the production | generation process of the application table which the control program of a platform layer performs. It is a schematic diagram which shows the structure which changed CPU into new CPU in the hierarchical structure shown in FIG. It is a schematic diagram which shows an example of the changed clock frequency table. It is a timing chart which shows an example of execution of an application program at the time of using a changed clock frequency table, and change of a clock frequency. It is a flowchart which shows the procedure of the creation process of the clock frequency table which the control program of a platform layer performs.

Explanation of symbols

1 CPU (processing device, computer)
1a CPU (processing device, computer)
2 Main storage unit 3 Input unit 4 Output unit 5 Auxiliary storage unit 6 Clock generation unit CP Control program (computer program)
AP, AP1-4 Application program AT application table (correspondence between application program and required processing capacity)
CT clock frequency table (correspondence between total required processing capacity and clock frequency)

Claims (7)

In the clock frequency control method for controlling the change of the clock frequency of the processing device that executes a plurality of application programs,
Store the correspondence between multiple application programs and the required processing capacity required to execute each application program.
Based on each required processing capability of one or more application programs executed in the processing device, to calculate the total required processing capability required to execute the one or more application programs,
Determine the clock frequency according to the calculated total required processing capacity,
A clock frequency control method, wherein the clock frequency of the processing device is changed to the determined clock frequency. Remember the correspondence between the total required processing power and the clock frequency,
The clock frequency control method according to claim 1, wherein the clock frequency to be changed is determined based on the calculated total required processing capacity, and the clock frequency to be changed is determined. Using a first control program according to the configuration of the processing device and a second control program for executing the application program,
Executing the first control program in the processing device;
Executing the second control program on the first control program;
Executing the application program on the second control program;
3. The clock frequency control method according to claim 2, wherein the total required processing capacity is calculated based on a correspondence between the application program and the required processing capacity in the second control program. 4. The clock frequency control method according to claim 3, wherein a correspondence between the application program and the required processing capacity is generated by the second control program in accordance with an application program executed by the processing device. 5. The clock frequency control method according to claim 3, wherein the second control program determines a clock frequency to be changed based on a correspondence between a total required processing capacity and a clock frequency. . 6. The clock frequency control method according to claim 5, wherein a correspondence between the total required processing capacity and the clock frequency is generated by the second control program in accordance with a processing device that executes an application program. In a computer program for causing a computer to control a change in clock frequency,
On the computer,
From the correspondence between the plurality of pre-stored application programs and the necessary processing capacity required to execute each application program, each necessary processing capacity of one or more application programs executed by the computer is acquired,
Based on each acquired required processing capacity, the total required processing capacity required to execute the one or more application programs is calculated,
The clock frequency is determined according to the calculated total required processing capacity,
A computer program for changing a clock frequency of the computer to a determined clock frequency.

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