com.digi.android.system.cpu

Class GovernorOnDemand

java.lang.Object

com.digi.android.system.cpu.Governor

com.digi.android.system.cpu.GovernorCommonBase

com.digi.android.system.cpu.GovernorOnDemand

public class GovernorOnDemand
extends GovernorCommonBase

Represents a governor of type 'ondemand'. This governor sets the CPU depending on the current usage.

This governor extends the GovernorCommonBase one, which includes a set of parameters that can be configured.

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_SAMPLING_DOWN_FACTOR Maximum sampling down factor: 100000.
static int	MIN_UP_THRESHOLD Minimum up threshold: 10.

Fields inherited from class com.digi.android.system.cpu.GovernorCommonBase

MAX_SAMPLING_RATE

Fields inherited from class com.digi.android.system.cpu.Governor

governorType, handler, PATH_GOVERNOR_SETTINGS

Method Summary

Modifier and Type	Method and Description
protected int	getSamplingDownFactorMaxValue() Returns the maximum limit for the sampling down factor.
protected java.lang.String	getTag() Returns the class tag used for logging purposes.
protected int	getUpThresholdMinValue() Returns the minimum limit for the up threshold percentage.
void	setSamplingDownFactor(int factor) Sets the sampling down factor.
void	setUpThreshold(int threshold) Sets the up threshold percentage.

Methods inherited from class com.digi.android.system.cpu.GovernorCommonBase

disableIgnoreNiceLoad, enableIgnoreNiceLoad, getIgnoreNiceLoad, getMinSamplingRate, getSamplingDownFactor, getSamplingRate, getUpThreshold, setSamplingRate

Methods inherited from class com.digi.android.system.cpu.Governor

getGovernorType, getSettingPath, readFile, writeFile

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MIN_UP_THRESHOLD

public static final int MIN_UP_THRESHOLD

Minimum up threshold: 10.

See Also:

Constant Field Values

MAX_SAMPLING_DOWN_FACTOR

public static final int MAX_SAMPLING_DOWN_FACTOR

Maximum sampling down factor: 100000.

See Also:

Constant Field Values

Method Detail

getTag

protected java.lang.String getTag()

Description copied from class: Governor

Returns the class tag used for logging purposes.

Specified by:

getTag in class Governor

Returns:

The class tag.

setUpThreshold

public void setUpThreshold(int threshold)
                    throws CPUException

Sets the up threshold percentage. Defines what the average CPU usage between the samplings of 'Sampling rate' needs to be for the kernel to make a decision on whether it should increase the frequency.

For example when it is set to its default value of '95' it means that between the checking intervals the CPU needs to be on average more than 95% in use to then decide that the CPU frequency needs to be increased.

Overrides:

setUpThreshold in class GovernorCommonBase

Parameters:

threshold - The up threshold percentage.

Throws:

CPUException - If there is an error during the configuration process.

java.lang.IllegalArgumentException - If threshold <= MIN_UP_THRESHOLD or if threshold > 100.

See Also:

MIN_UP_THRESHOLD, GovernorCommonBase.getUpThreshold()

setSamplingDownFactor

public void setSamplingDownFactor(int factor)
                           throws CPUException

Sets the sampling down factor. This parameter controls the rate at which the kernel makes a decision on when to decrease the frequency while running at top speed. When set to 1 (the default) decisions to reevaluate load are made at the same interval regardless of current clock speed. But when set to greater than 1 (e.g. 10) it acts as a multiplier for the scheduling interval for reevaluating load when the CPU is at its top speed due to high load.

Overrides:

setSamplingDownFactor in class GovernorCommonBase

Parameters:

factor - The new sampling down factor.

Throws:

CPUException - If there is an error during the configuration process.

java.lang.IllegalArgumentException - If factor < 1 or if factor > MAX_SAMPLING_DOWN_FACTOR.

See Also:

MAX_SAMPLING_DOWN_FACTOR, GovernorCommonBase.getSamplingDownFactor()

getSamplingDownFactorMaxValue

protected int getSamplingDownFactorMaxValue()

Description copied from class: GovernorCommonBase

Returns the maximum limit for the sampling down factor.

Specified by:

getSamplingDownFactorMaxValue in class GovernorCommonBase

Returns:

the maximum limit for the sampling down factor.

getUpThresholdMinValue

protected int getUpThresholdMinValue()
                              throws CPUException

Description copied from class: GovernorCommonBase

Returns the minimum limit for the up threshold percentage.

Specified by:

getUpThresholdMinValue in class GovernorCommonBase

Returns:

the minimum limit for the up threshold.

Throws:

CPUException - If there is an error while calculating the minimum limit.