KR101807412B1 - Apparatus and method for managing power consumption using processor occupation restriction - Google Patents

Abstract

A power management apparatus and method with processor occupancy limitation is provided. A power management apparatus according to an exemplary embodiment of the present invention includes a user-centric control unit for obtaining and providing a current processor occupancy rate of a target application and a current frame rate of a target application in a current sampling interval, An upper limit occupancy setting unit configured to set a processor occupancy upper limit of a next sampling interval according to a result of comparing a size of the current frame rate with a threshold frame rate of an upper limit critical frame rate and a lower limit threshold frame rate, The occupancy rate setting unit sets the occupation rate of the processor in a state where the operating speed of the processor is unchanged, based on at least one of a current scaling factor, a current process occupancy upper limit, the current frame rate, And sets the processor occupancy upper limit of the next sampling period.

Description

[0001] APPARATUS AND METHOD FOR MANAGING POWER CONSUMPTION USING PROCESSOR OCCUPATION RESTRICTION [0002]

The present invention relates to a power management apparatus and method, and more particularly, to an apparatus and method for managing power using a processor occupancy limitation.

The hard real-time system proposes optimal scheduling algorithms on the assumption that the target programs are characterized, but most systems are changing close to the desk-tam operating system, except for systems where stability is very important.

A typical example is the smartphone operating system, which is based on the Linux-based Android operating system, and because it is an open environment for downloading various programs from the application market, hard real-time System-based technology is not expected to have a significant effect and is not actually used.

A power management system considering a user experience has been used to increase or decrease the operation speed of the processor in order to reduce the power consumption. However, since the two or more tasks can be executed in one processor, There is a limitation in that the power management performed by the processor can affect the performance of all the tasks executed by the processor.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of managing power by using an occupancy limitation of a processor without changing the operating speed of the processor.

In order to achieve the above object, a power management apparatus according to an exemplary embodiment of the present invention includes: a user-centered control unit for obtaining a current frame rate of a target application and a current processor occupancy rate for execution of the target application in a current sampling interval, A processor occupancy upper limit of the next sampling interval is set according to a result of comparing a size of the current frame rate with a threshold frame rate for setting a lower processor occupancy upper limit and an upper limit threshold frame rate and a lower threshold frame rate for setting a processor occupancy upper limit Wherein the upper occupancy rate setting unit is configured to set the upper limit occupancy setting unit based on at least one of a current scaling factor, a current process occupancy upper limit, the current frame rate, and a current processor occupation rate, While degrees unchanged characterized in that to set the upper limit of the processors share the next sampling interval.

According to another aspect of the present invention, there is provided a power management apparatus for, when a user event for a target application occurs in a current sampling interval, a priority weight corresponding to the user event, And an upper limit occupancy rate setting unit for setting a processor occupancy upper limit of a next sampling interval in a state in which the operating speed of the processor is unchanged according to a result of comparing threshold values for initializing the occupancy upper limit, And if the weighting value is greater than or equal to the threshold value, initializes a processor occupancy upper limit of the next sampling interval, and if the priority weighting value is equal to or smaller than the threshold value, Setting And a gong.

In order to achieve the above object, a method for a power management apparatus according to an exemplary embodiment of the present invention for managing power using an occupancy limitation of a processor includes the steps of: (a) Obtaining a current processor occupancy for the execution of the processor frame; and (b) comparing the size of the current frame rate with a threshold frame rate-an upper limit threshold frame rate and a lower limit threshold frame rate for setting a processor occupancy upper limit - Wherein the step (b) comprises: setting a processor occupancy upper limit for a next sampling interval, in accordance with the current processor occupancy rate upper limit, the current processor occupancy upper limit, the current scaling factor, Based on one or more of the occupancy, While the operating speed is unchanged, it is characterized in that setting the upper limit of the processors share the next sampling interval.

According to another aspect of the present invention, there is provided a method for managing a power using a processor occupancy restriction, the method comprising the steps of: (a) determining whether a user event has occurred for a target application; (b) if a user event occurs as a result of the determination, comparing a priority weight corresponding to the user event with a threshold value for initializing a processor occupancy upper limit, (B) initializing a processor occupancy upper limit of the next sampling interval if the priority weight is greater than the threshold, and setting the processor occupancy upper limit of the next sampling interval And if it is equal to or smaller than the threshold value, It characterized by setting the upper limit ratio to the previous sampling interval of the processors share the upper limit value.

According to an embodiment of the present invention, power consumption can be reduced without changing the operating speed of the processor.

In addition, maximum power consumption control and energy consumption reduction are possible.

It should be understood that the effects of the present invention are not limited to the above effects and include all effects that can be deduced from the detailed description of the present invention or the configuration of the invention described in the claims.

1 is a diagram illustrating a configuration of a power management apparatus according to an embodiment of the present invention.
2 is a flowchart illustrating a power management process according to an embodiment of the present invention.
3 is a flowchart illustrating a power management process according to another embodiment of the present invention.
4 is a graph illustrating the relationship between quota and power management according to an embodiment of the present invention.
5 is a test result of a power management method according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "indirectly connected" .

Also, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating a configuration of an apparatus for managing power using an occupancy limitation of a processor according to an embodiment of the present invention. Referring to FIG.

For reference, the CPU is described as an embodiment of the 'processor', but the processor is not limited to the CPU alone.

CPU processing performance can be controlled by the CPU clock frequency, and most mobile vendors provide a Dynamic Voltage and Frequency Scaling (DVFS) interface to adjust the clock frequency and supply voltage during runtime.

However, changing the clock frequency of the CPU may affect the execution of all applications running on the CPU.

That is, if the clock frequency of the CPU is lowered to reduce the power consumption during execution of the target application, serious problems occur such as a decrease in the user experience (hereinafter referred to as "UX") of other applications running on the same CPU .

On the contrary, when the CPU clock frequency is increased, the CPU processing performance can be improved, but the power consumption is increased accordingly.

Thus, there is a need for control of the CPU processing performance for satisfactory execution of all currently executing applications (e.g., maintaining an appropriate UX level).

Accordingly, the present invention intends to utilize the CPU occupancy limitation for the target application as an efficient way to reduce the power consumption of the CPU while maintaining the quality of UX without changing the clock frequency of the CPU.

The power management apparatus 100 according to an exemplary embodiment of the present invention includes a user-centric governor (UCG) 110, a CPU Bandwidth Control (CPU BWC) 120, And a dynamic frequency and frequency scaling (DVFS)

The user centric control unit (UCG) 110 obtains the CPU utilization rate of the target application and the execution rate of the target application displayed on the screen, (CPU BWC) 120 and a dynamic voltage / frequency setting unit (DVFS) 130.

For this, the user centric control unit (UCG) 110 may monitor the frame rate.

Here, 'frame rate' can be a key metric for measuring the quality of UX, and monitoring the frame rate is very important to achieve satisfactory UX quality for the end user.

Accordingly, the user centric control unit (UCG) 110 may use an access count of the frame buffer to monitor the frame rate without interrupting the execution of the target application.

That is, a frame buffer interrupt occurs whenever one frame is displayed on the screen, and the user-centered control unit (UCG) 110 can measure the frame rate by monitoring the frame buffer interrupt.

In this regard, the user centric control unit (UCG) 110 may measure the frame rate by performing an access count every predetermined period (e.g., 100 ms or 200 ms), and may determine the most recent samples ) To measure the frame rate.

For reference, a graphical application is in an idle, interactive, or highly interactive state while the application is running.

Here, the 'idle state' is a state in which there is no change in the display, for example, when the data is loaded or waiting state for the user's input.

The 'interactive state' is a state in which the display changes but has a frame rate in the range of 1 to 50 fps.

For reference, the frame rate for executing the multimedia service is generally 30 fps or more.

The 'highly interactive state' is a state in which the display changes but has a frame rate of 50 fps or more.

For reference, most applications attempt to refresh the display periodically (very frequently) to ensure the high quality of UX in highly interactive situations.

While graphics applications are running in this state, the frame rate can be run at a level exceeding 45 fps (about 60 fps).

For reference, 60 fps is above the level at which human eyes can perceive the difference in image quality, and in fact end users are not aware of the large difference in image quality between 45 fps and 60 fps.

As a result, a high frame rate exceeding 45 fps may unnecessarily consume excessive power, thereby reducing CPU processing performance.

The user centric control unit (UCG) 110 is capable of performing tasks by graphics applications in an interactive or highly interactive state. The user centric control unit (UCG) 110 controls the upper bound occupancy rate setting unit (CPU BWC) 120 and the dynamic voltage / Frequency setting unit (DVFS) 130 can be used to adjust the CPU processing performance.

Meanwhile, the upper limit occupancy setting unit (CPU BWC) 120 may set an upper limit (hereinafter referred to as 'Quota') of the CPU occupation rate for the target application requiring graphics processing.

At this time, the upper limit occupancy setting unit (CPU BWC) 120 sets a frame rate (hereinafter referred to as 'cur_FPS') of the current sampling period (hereinafter referred to as 'current'), a current CPU occupation rate and a scaling factor Based on at least one of a lower limit threshold value (hereinafter referred to as 'dThr_FPS') or an upper limit threshold value (hereinafter referred to as 'uThr_FPS') of a frame rate for setting a current C value and a quota, Quot; hereinafter).

Here, 'C value' is a scaling factor of positive that has a value between 0.1 and 0.1, and increases or decreases by 0.1 interval, as a decreasing rate of CPU occupancy.

In one embodiment, the upper bound occupancy setting unit (CPU BWC) 120 compares the sizes of cur_FPS and dThr_FPS, and keeps the subsequent quota at the current quota or further compares the sizes of cur_FPS and dThr_FPS according to the result .

Then, according to the comparison result, a later quota can be set using the current CPU occupancy rate and the current C value, or the minimum value of the function having the current quota and the current CPU occupancy rate as parameters can be set as the subsequent quota.

A detailed description thereof will be given later with reference to Fig.

In another embodiment, the upper bound occupancy setting unit (CPU BWC) 120 may be configured to reflect the importance of the indicator indicating UX for an application program (e.g., a web browser, a text editor, etc.) The subsequent quota can be reset (releasing quota) or returned to the quota value of the previous sampling period (hereinafter referred to as " previous ")

For reference, UX indicates performance that the user experiences, and may mean subjective but measurable values such as frame rate and touch response rate.

The 'importance of the index indicating the UX' may be defined as a weight function according to UX requiring high reactivity such as touch screen input.

For example, if the user does not input any touch on the touch screen, the user can gradually set a later quota based on the average CPU occupancy rate, and initialize the subsequent quota if the input through the touch screen occurs . That is, for the high reactivity, the following quota is initialized and newly started.

Then, for the index indicating UX other than the touch screen input, the subsequent quota can be returned to the previous value.

For this purpose, the upper occupancy rate setting unit (CPU BWC) 120 may use the following function to initialize the quota or return to the previous value according to the importance of the index indicating UX.

[Table 1]

The upper limit occupancy rate setting unit (CPU BWC) 120 sets a threshold value (hereinafter referred to as 'pThr') for initializing 'Quota', which is a reference value for determining whether the quota is initialized or returned to a previous value Can be set.

Note that if the previous performance can be compensated without initializing the quota, restoring the quota to the previous value can save more power.

A detailed description thereof will be given later with reference to Fig.

On the other hand, the dynamic voltage / frequency setting unit (DVFS) 130 can set a subsequent CPU frequency based on the current CPU frequency and the current CPU occupation rate.

For reference, power consumption modeling according to the quota of the processor by the power management apparatus 100 according to an embodiment of the present invention can be expressed by the following equation.

[Equation 1]

P = C * V * F ² - > P _new = P (? +? Q)

Where P is power consumption,

F is the operating clock frequency,

V is the supply voltage,

Q is the upper bound of CPU utilization; Quota

? and? are positive numbers.

This means that when the quota is set to be lower than the average occupancy rate of the target program regardless of the values of [alpha] and [beta], the power consumption of the processor consumed by the program also decreases proportionally as the quota is lowered.

2 is a flowchart illustrating a power management process according to an embodiment of the present invention.

2 is a process for reducing a power consumption of a processor by setting a quota for a target application according to cur_FPS.

First, the power management apparatus 100 confirms the current quota value and the current C value (S201).

For reference, the quota value and the C value of S201 are states in which cur_FPS is smaller than dThr_FPS of the target application, the quota value is -1, and the C value is 1. [

After S201, the power management apparatus 100 periodically compares cur_FPS and dThr_FPS (S202). If cur_FPS is less than dThr_FPS, the current quota value and the C value are maintained. If cur_FPS is equal to dThr_FPS or greater than dThr_FPS, cur_FPS The size of uThr_FPS is compared (S203).

If cur_FPS is greater than uThr_FPS as a result of comparison, the power management apparatus 100 applies the C value to the current CPU occupation rate to set a subsequent quota (S204).

In one embodiment, the power management apparatus 100 may set the quota by multiplying the current CPU utilization by the C value.

After S204, the power management apparatus 100 adjusts the C value by applying a constant value to the C value (S205).

In one embodiment, the power management apparatus 100 may subtract a particular value (0.1) from the C value.

Here, 'C value' is a positive scaling factor having a value between 0.1 and C? 1 and increasing or decreasing by 0.1 interval, and the power management apparatus 100 uses (adjusts) the C value The power consumption of the CPU can be reduced.

If cur_FPS is equal to uThr_FPS or less than uThr_FPS as a result of the comparison in S203, the power management apparatus 100 may set the minimum value of the function having the current quota and the CPU occupancy as parameters as the following quota (S206).

The power management apparatus 100 may perform cur_FPS to be smaller than dThr_FPS by repeating the processes of S202 and subsequent steps after S205 or S206, or may cause cur_FPS to be kept within the range of dThr_FPS and uThr_FPS.

3 is a flowchart illustrating a power management process according to another embodiment of the present invention.

3 is a process for setting a quota for an application program in which the graphical processing is not frequent but the user reactivity is important, such as a touch response rate.

The power management apparatus 100 determines whether user driven events such as touch input have occurred (S301).

If it is determined that no user event has occurred, the power management apparatus 100 applies the C value to the current CPU occupancy rate (multiplied) to determine a subsequent quota (S302).

After S302, the power management apparatus 100 adjusts the C value by applying a constant value to the C value (S303).

If it is determined in step S301 that the user event has occurred, the power management apparatus 100 calculates a priority weight for the user event (S304).

Here, the 'priority weighting' can be calculated using the priority weighting function as a criterion used for determining whether to initialize the quota or return to the previous value according to the importance of the index indicating UX, As shown in Table 1.

After step S304, the power management apparatus 100 compares the priority weight with a preset threshold for initializing the quota (hereinafter, referred to as 'pThr') (S305), and initializes or returns the quota .

For example, if the priority weight is greater than pThr, i.e., UX requiring high responsiveness, the quota is initialized (S306).

If the priority weight is equal to pThr or greater than pThr, i.e., UX that does not require high reactivity, the quota is returned to the previous value (S307).

For reference, in S307, when returning the quota to the previous value, a value obtained by applying a constant value to a current C value and a minimum value of a function using a predetermined constant (for example, 0.9) as a C value Quot ;, and dividing the current quota by the set C value, the quota can be returned to the previous value.

4 is a graph illustrating the relationship between quota and power management according to an embodiment of the present invention.

Figure 4 shows the average power consumption at various quotations from 100% to 10% per CPU frequency (600 MHz and 300 MHz).

As shown in FIG. 4, it can be seen that the average power consumption of the CPU decreases according to the quota, and in particular, when the quota is smaller than the specific value, the average power consumption decreases with the quota Quota less than 60%).

Hereinafter, a test result of the power management scheme according to an embodiment of the present invention will be described with reference to FIG.

For reference, the following tests are performed on the Odroid XUE board, which includes four sensors to measure the power consumption of the Cortex-A15 cores, Cortex-A7 cores, GPUs, and DRAMs. The Android 4.3.3 Jelly Bean and the Linux kernel 3.4.5 was used as the operating system.

Most graphics applications operate in idle, interactive, or highly interactive states, where the behavior of the application in each state can be detected by monitoring the frame rate.

The power consumption and frame rate are monitored when the target application is running in an interactive or highly interactive state.

Here, 'power consumption' and 'frame rate' are measured during the execution of three kinds of programs, one is a multimedia program, the other is a mobile game, and the other is a benchmark program.

In the test of FIG. 5, the threshold frame rate (fThr) for the multimedia program is 30 fps and the threshold frame rate (fThr) for the remaining programs, i.e., mobile games and benchmark programs, is 45 fps.

Here, 'critical frame rate (fThr)' means the minimum frame rate for satisfying the UX of the end user.

For reference, these frame rates are values commonly used in video games and mobile games.

Also, the degradation of UX in the test of FIG. 5 can be measured by comparing the end user's satisfaction rate by counting how often the frame rate falls below the threshold frame rate (fThr).

As examples of the above three programs, the multimedia program uses YouTube streaming, the mobile game uses Aagry Birds Space, and the benchmark program uses Epic Citadel.

Here, YouTube video streaming is a well-known multimedia service that reproduces images with a running time of 60 seconds.

In addition, Angry Birdspace is a well-known mobile game that has been monitored for 60 seconds of play.

In addition, the Epic Citadel is a demonstration of Unreal Engine 3's technical capabilities, with a running time of 110 seconds.

Many graphics applications drastically process (remove) delayed frames to process new frames at a fixed time, and likewise, the test of the present invention assumes that the execution time does not increase (not delayed) when graphics applications are executed .

Accordingly, the running time and play time of each of the programs may be fixed to 60 seconds, 60 seconds, and 110 seconds.

In addition, each sampling interval is 200ms, and the clock frequency of the CPU and the GPU are fixed and unchanged.

5 is a test result showing a decrease in power consumption according to the adjustment of the C value of the upper limit occupancy rate setting unit (CPU BWC) 120 in a state where the clock frequency of the CPU is fixed, and the quality of UX is maintained The power consumption can be further reduced.

Compared with the conventional method, it can be seen that the power consumption is reduced by 70% without decreasing the UX in the YouTube image when the C value is 0.2.

In addition, the power consumption of the Angry Bird and Epic Citadel is reduced by 32% with a slight decrease in UX compared to the conventional method (Angry Bird has a C value of 0.7, a UX decrease of 0, an Epic Citadel The C value is 0.9, and the UX reduction is 1).

Note that applying a lower C value will result in a lower CPU power consumption but a further reduction in UX.

For example, Angry Bird and Epic Citadel have shown a significant decline in UX at low values of C (0.2) (Angry Bird has a UX decrease of 43 at a C value of 0.2 and a UX decline at a C value of 0.2 for an Epic Citadel. to be).

Therefore, it is not desirable to select an unconditionally low value of C, and it is important to select a C value that can reduce CPU power consumption while considering UX reduction.

Also, the average GPU power consumption of YouTube according to the decrease of the C value does not differ greatly because the graphics processor is rarely used.

However, the average GPU power consumption of the other two programs decreases sharply as C decreases from 1 to 0.2.

This is because most mobile games (Angry Birds) and graphics engines (Epic Citadel) use both CPUs and GPUs at the same time that they generate each frame, and GPU usage can be reduced by lower CPU usage.

5 also shows that the upper bound occupancy setting unit (CPU BWC) 120 can reduce the average GPU power consumption.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: power management device
110: user-centered control unit
120: upper limit occupancy rate setting unit
130: Dynamic voltage / frequency setting unit

Claims (17)

A power management apparatus comprising:
A user-centered controller for obtaining and providing a current frame rate of a target application and a current processor occupancy rate for execution of the target application in a current sampling interval; And
An upper limit occupancy rate setting unit for setting a processor occupancy upper limit of a next sampling period according to a result of comparing a size of the current frame rate with a critical frame rate for setting a processor occupancy upper limit - an upper limit critical frame rate and a lower limit critical frame rate, Setting section
, ≪ / RTI &
The upper occupancy rate setting unit
The processor of the next sampling interval, with the operating speed of the processor unchanged, based on at least one of a current scaling factor, a current process occupancy upper limit, the current frame rate, and a current processor occupancy, The upper limit of the occupancy rate is set,
The upper occupancy rate setting unit
If the current frame rate is within the range of the critical frame rate,
Wherein the minimum value of the function having the current processor occupancy upper limit and the current processor occupancy rate as parameters is set to the processor occupancy upper limit of the next sampling period.
delete The method according to claim 1,
The upper occupancy rate setting unit
If the current frame rate is out of the range of the threshold frame rate and is greater than the upper threshold frame rate,
And sets a value obtained by multiplying the current processor occupancy rate by a current scaling factor to an upper processor occupancy rate of the next sampling interval.
The method of claim 3,
The upper occupancy rate setting unit
Subtracts a predetermined adjustment value for the scaling factor C from the current scaling factor, and sets the resultant value as a scaling factor of a next sampling interval.
The method according to claim 1,
The upper occupancy rate setting unit
If the current frame rate is out of the range of the threshold frame rate and is smaller than the lower threshold frame rate,
And sets the processor occupancy upper limit and the scaling factor of the next sampling interval as the current processor occupancy upper limit and the current scaling factor value.
The method according to claim 1,
The user-
Acquiring the frame rate using an access count of a frame buffer at a predetermined period or obtaining the frame rate using an access count of a frame buffer for a predetermined number of samples.
A power management apparatus comprising:
When a user event for the target application occurs in the current sampling interval, a threshold value for initializing the processor occupancy upper limit is compared with a priority weight corresponding to the user event. A maximum occupancy rate setting unit for setting a maximum processor occupancy rate of the next sampling period
, ≪ / RTI &
The upper occupancy rate setting unit
If the priority weight is greater than the threshold value, initialize the processor occupancy upper limit of the next sampling interval,
And sets the processor occupancy upper limit of the next sampling interval to the processor occupancy upper limit value of the previous sampling interval if the priority weight is equal to or smaller than the threshold value.
8. The method of claim 7,
A user-centered control unit for acquiring and providing a current processor occupancy rate in a current sampling interval,
Further comprising:
The upper occupancy rate setting unit
And sets a value obtained by multiplying a current scaling factor, which is a reduction ratio of the processor occupancy rate, with the current processor occupancy rate, to the processor occupancy upper limit of the next sampling period if the user event does not occur.
9. The method of claim 8,
The upper occupancy rate setting unit
Subtracts a predetermined adjustment value for the scaling factor C from the current scaling factor, and sets the result as a scaling factor of a next sampling interval.
8. The method of claim 7,
The upper occupancy rate setting unit
A value obtained by adding a predetermined adjustment value (a constant value for the scaling factor C) to a current scaling factor which is a reduction rate of the processor occupancy rate and a minimum value of a function having a predetermined constant as a parameter are scaled Factor,
Dividing the current processor occupancy upper limit by a scaling factor of the next sampling interval, and setting an upper processor occupancy rate of the next sampling interval to an upper processor occupancy rate of the previous sampling interval.
CLAIMS 1. A method for a power management device to manage power using an occupancy limitation of a processor,
(a) obtaining a current frame rate of a target application and a current processor occupancy for execution of the target application in a current sampling interval; And
(b) a processor occupancy upper limit of a next sampling interval is set according to a result of comparing a size of the current frame rate with a threshold frame rate for setting a processor occupancy upper limit - an upper limit critical frame rate and a lower limit threshold frame rate, Step
, ≪ / RTI &
The step (b)
The processor of the next sampling interval, with the operating speed of the processor unchanged, based on at least one of a current scaling factor, a current process occupancy upper limit, the current frame rate, and a current processor occupancy, The upper limit of the occupancy rate is set,
The step (b)
If the current frame rate is within the range of the critical frame rate,
Wherein the minimum value of the function having the current processor occupancy upper limit and the current processor occupancy rate as parameters is set as the processor occupancy upper limit of the next sampling period.
delete 12. The method of claim 11,
The step (b)
If the current frame rate is out of the range of the threshold frame rate and is greater than the upper threshold frame rate,
Setting a value obtained by multiplying the current processor occupancy rate by a current scaling factor to an upper processor occupancy rate of the next sampling interval,
Subtracting a predetermined adjustment value for the scaling factor C from the current scaling factor, and setting the resultant value as a scaling factor of a next sampling interval.
12. The method of claim 11,
The step (b)
If the current frame rate is out of the range of the threshold frame rate and is smaller than the lower threshold frame rate,
And setting a processor occupancy upper limit and a scaling factor of the next sampling interval as the current processor occupancy upper limit and a current scaling factor value.
CLAIMS 1. A method for a power management device to manage power using an occupancy limitation of a processor,
(a) determining whether a user event has occurred for a target application; And
(b) if a user event occurs as a result of the determination, comparing a priority weight corresponding to the user event with a threshold value for initializing a processor occupancy upper limit, A step of setting a processor occupancy upper limit of a next sampling interval
, ≪ / RTI &
The step (b)
If the priority weight is greater than the threshold value, initialize the processor occupancy upper limit of the next sampling interval,
Wherein if the priority weight is equal to or smaller than the threshold value, the processor occupancy upper limit of the next sampling period is set to the processor occupancy upper limit value of the previous sampling period.
16. The method of claim 15,
Before the step (a)
Acquiring the current processor occupancy rate in the current sampling interval
Further comprising:
The step (b)
Setting a value obtained by multiplying a current scaling factor, which is a decreasing rate of the processor occupancy rate, and the current processor occupancy rate, to a processor occupancy upper limit of the next sampling period,
Subtracting a predetermined adjustment value for the scaling factor C from the current scaling factor and setting the result as a scaling factor of a next sampling interval.
16. The method of claim 15,
The step (b)
A value obtained by adding a predetermined adjustment value (a constant value for the scaling factor C) to a current scaling factor which is a reduction rate of the processor occupancy rate and a minimum value of a function having a predetermined constant as a parameter are scaled Factor,
Dividing the current processor occupancy upper limit by a scaling factor of the next sampling interval, and setting an upper processor occupancy rate of the next sampling interval to an upper processor occupancy rate of the previous sampling interval.

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