现象
以下是BugReport日志
日志
STATE_ACTIVE
2,006: 11-17 10:24:59.876137 900 900 I DeviceIdleController: updateChargingLocked: charging=true
2,007: 11-17 10:24:59.876244 900 900 I DeviceIdleController: becomeActiveLocked, reason = charging
2,258: 11-17 10:25:35.586856 900 1037 D DeviceIdleController: handleMessage(7)
2,285: 11-17 10:25:35.629342 900 1037 D DeviceIdleController: handleMessage(7)
2,663: 11-17 10:26:04.366455 900 900 I DeviceIdleController: updateChargingLocked: charging=false
3,823: 11-17 10:26:08.494908 900 900 D DeviceIdleController: updateDisplayLocked: screenOn=false STATE_ACTIVE to STATE_INACTIVE
条件：
暗屏，不充电即可
3,824: 11-17 10:26:08.495002 900 900 D DeviceIdleController: becomeInactiveIfAppropriateLocked()
3,825: 11-17 10:26:08.495032 900 900 D DeviceIdleController: Moved from STATE_ACTIVE to STATE_INACTIVE
3,826: 11-17 10:26:08.495209 900 900 D DeviceIdleController: stopMonitoringMotionLocked()
// 3 分钟 INACTIVE_TIMEOUT
3,827: 11-17 10:26:08.495311 900 900 D DeviceIdleController: scheduleAlarmLocked(180000, false)
3,829: 11-17 10:26:08.495907 900 900 D DeviceIdleController: Moved from LIGHT_STATE_ACTIVE to LIGHT_STATE_INACTIVE
// 15 秒
3,830: 11-17 10:26:08.495967 900 900 D DeviceIdleController: scheduleLightAlarmLocked(15000)
3,831: 11-17 10:26:08.498412 900 900 V AlarmManager: APP set with listener(DeviceIdleController.light) : type=2 triggerAtTime=3649013 win=-1 tElapsed=3649013 maxElapsed=3660261 interval=0 flags=0x8 // 11-17 10:26:25 减去 11-17 10:26:08 过了17秒
3,987: 11-17 10:26:25.015547 900 1064 D AlarmManager: wakeup alarm = Alarm{2ef114b type 2 when 3649013 android}; listener package = DeviceIdleController.lightneedGrouping = false
/** Device is inactive (screen off) and we are waiting to for the first light idle. */
// private static final int LIGHT_STATE_INACTIVE = 1;
3,988: 11-17 10:26:25.015989 900 1037 D DeviceIdleController: stepLightIdleStateLocked: mLightState=1
// 15 秒
3,990: 11-17 10:26:25.016176 900 1037 D DeviceIdleController: scheduleLightAlarmLocked(15000)
3,992: 11-17 10:26:25.017253 900 1037 V AlarmManager: APP set with listener(DeviceIdleController.light) : type=2 triggerAtTime=3665533 win=-1 tElapsed=3665533 maxElapsed=3676782 interval=0 flags=0x8 /** Device is in the light idle state, trying to stay asleep as much as possible. */
// private static final int LIGHT_STATE_IDLE = 4;
3,994: 11-17 10:26:25.017778 900 1037 D DeviceIdleController: Moved to LIGHT_STATE_IDLE.
// private static final int MSG_REPORT_IDLE_ON_LIGHT = 3;
3,996: 11-17 10:26:25.018157 900 1037 D DeviceIdleController: handleMessage(3) // 11-17 10:26:41 减去 11-17 10:26:25 过了6秒
4,786: 11-17 10:26:41.010752 900 1064 D AlarmManager: wakeup alarm = Alarm{fc74c41 type 2 when 3665533 android}; listener package = DeviceIdleController.lightneedGrouping = false
4,790: 11-17 10:26:41.017345 900 1037 D DeviceIdleController: stepLightIdleStateLocked: mLightState=4
4,791: 11-17 10:26:41.017503 900 1037 D DeviceIdleController: scheduleLightAlarmLocked(30000)
4,792: 11-17 10:26:41.017854 900 1037 V AlarmManager: APP set with listener(DeviceIdleController.light) : type=2 triggerAtTime=3696534 win=-1 tElapsed=3696534 maxElapsed=3719033 interval=0 flags=0x8
// We'd like to do maintenance, but currently don't have network
// connectivity... let's try to wait until the network comes back.
// We'll only wait for another full idle period, however, and then give up./** Device is in the light idle state, we want to go in to idle maintenance but are
* waiting for network connectivity before doing so. */
// private static final int LIGHT_STATE_WAITING_FOR_NETWORK = 5;
4,793: 11-17 10:26:41.018638 900 1037 D DeviceIdleController: Moved to LIGHT_WAITING_FOR_NETWORK. 4,868: 11-17 10:27:12.026656 900 1064 D AlarmManager: wakeup alarm = Alarm{aedfc2c type 2 when 3696534 android}; listener package = DeviceIdleController.lightneedGrouping = false
//LIGHT_STATE_WAITING_FOR_NETWORK = 5;
4,870: 11-17 10:27:12.027149 900 1037 D DeviceIdleController: stepLightIdleStateLocked: mLightState=5
// 15 秒
4,872: 11-17 10:27:12.028098 900 1037 D DeviceIdleController: scheduleLightAlarmLocked(15000)
4,873: 11-17 10:27:12.028447 900 1037 V AlarmManager: APP set with listener(DeviceIdleController.light) : type=2 triggerAtTime=3712545 win=-1 tElapsed=3712545 maxElapsed=3723795 interval=0 flags=0x8 // 等待应用窗口事件被触发
4,876: 11-17 10:27:12.028905 900 1037 D DeviceIdleController: Moved from LIGHT_STATE_IDLE to LIGHT_STATE_IDLE_MAINTENANCE.
// private static final int MSG_REPORT_IDLE_OFF = 4;
4,879: 11-17 10:27:12.032376 900 1037 D DeviceIdleController: handleMessage(4)
// private static final int MSG_REPORT_MAINTENANCE_ACTIVITY = 7;
5,620: 11-17 10:27:12.509524 900 1037 D DeviceIdleController: handleMessage(7)
5,651: 11-17 10:27:12.516501 900 1037 D DeviceIdleController: handleMessage(7)
// private static final int MSG_FINISH_IDLE_OP = 8;
5,652: 11-17 10:27:13.517743 900 1037 D DeviceIdleController: handleMessage(8)
5,653: 11-17 10:27:13.517875 900 1037 D DeviceIdleController: Exit: start=+1h1m37s545ms now=+1h1m39s35ms
/** Device is in the idle state, but temporarily out of idle to do regular maintenance. */
// private static final int STATE_IDLE_MAINTENANCE = 6;
5,654: 11-17 10:27:13.517936 900 1037 D DeviceIdleController: stepLightIdleStateLocked: mLightState=6
5,655: 11-17 10:27:13.518107 900 1037 D DeviceIdleController: scheduleLightAlarmLocked(30000)
5,656: 11-17 10:27:13.518371 900 1037 V AlarmManager: APP set with listener(DeviceIdleController.light) : type=2 triggerAtTime=3729035 win=-1 tElapsed=3729035 maxElapsed=3751535 interval=0 flags=0x8 // IDLE_MAINTENANCE 和 STATE_IDLE 是不断交替进行的，IDLE下应用特性会被限制
5,661: 11-17 10:27:13.523054 900 1037 D DeviceIdleController: Moved to LIGHT_STATE_IDLE.
5,663: 11-17 10:27:13.523870 900 1037 D DeviceIdleController: handleMessage(3) 时间设定
package com.android.server;/*** Keeps track of device idleness and drives low power mode based on that.*/
public class DeviceIdleController extends SystemServiceimplements AnyMotionDetector.DeviceIdleCallback {private static final boolean DEBUG = true;private static final boolean COMPRESS_TIME = true;private void updateConstants() {synchronized (DeviceIdleController.this) {try {mParser.setString(Settings.Global.getString(mResolver,mHasWatch ? Settings.Global.DEVICE_IDLE_CONSTANTS_WATCH: Settings.Global.DEVICE_IDLE_CONSTANTS));} catch (IllegalArgumentException e) {// Failed to parse the settings string, log this and move on// with defaults.Slog.e(TAG, "Bad device idle settings", e);}// 5 分钟 或者 15 秒LIGHT_IDLE_AFTER_INACTIVE_TIMEOUT = mParser.getLong(KEY_LIGHT_IDLE_AFTER_INACTIVE_TIMEOUT,!COMPRESS_TIME ? 5 * 60 * 1000L : 15 * 1000L);// 10 分钟 或者 30 秒LIGHT_PRE_IDLE_TIMEOUT = mParser.getLong(KEY_LIGHT_PRE_IDLE_TIMEOUT,!COMPRESS_TIME ? 10 * 60 * 1000L : 30 * 1000L);// 5 分钟 或者 15 秒LIGHT_IDLE_TIMEOUT = mParser.getLong(KEY_LIGHT_IDLE_TIMEOUT,!COMPRESS_TIME ? 5 * 60 * 1000L : 15 * 1000L);LIGHT_IDLE_FACTOR = mParser.getFloat(KEY_LIGHT_IDLE_FACTOR,2f);// 15 分钟 或者 60 秒LIGHT_MAX_IDLE_TIMEOUT = mParser.getLong(KEY_LIGHT_MAX_IDLE_TIMEOUT,!COMPRESS_TIME ? 15 * 60 * 1000L : 60 * 1000L);// 1 分钟 或者 15 秒LIGHT_IDLE_MAINTENANCE_MIN_BUDGET = mParser.getLong(KEY_LIGHT_IDLE_MAINTENANCE_MIN_BUDGET,!COMPRESS_TIME ? 1 * 60 * 1000L : 15 * 1000L);// 5 分钟 或者 30 秒LIGHT_IDLE_MAINTENANCE_MAX_BUDGET = mParser.getLong(KEY_LIGHT_IDLE_MAINTENANCE_MAX_BUDGET,!COMPRESS_TIME ? 5 * 60 * 1000L : 30 * 1000L);// 5 分钟 或者 1 秒MIN_LIGHT_MAINTENANCE_TIME = mParser.getLong(KEY_MIN_LIGHT_MAINTENANCE_TIME,!COMPRESS_TIME ? 5 * 1000L : 1 * 1000L);// 30 秒 或者 5 秒MIN_DEEP_MAINTENANCE_TIME = mParser.getLong(KEY_MIN_DEEP_MAINTENANCE_TIME,!COMPRESS_TIME ? 30 * 1000L : 5 * 1000L);long inactiveTimeoutDefault = (mHasWatch ? 15 : 30) * 60 * 1000L;// 30 分钟 或者 3 分钟INACTIVE_TIMEOUT = mParser.getLong(KEY_INACTIVE_TIMEOUT,!COMPRESS_TIME ? inactiveTimeoutDefault : (inactiveTimeoutDefault / 10));// 4 分钟 或者 15 秒SENSING_TIMEOUT = mParser.getLong(KEY_SENSING_TIMEOUT,!DEBUG ? 4 * 60 * 1000L : 60 * 1000L);// 30 秒 或者 15 秒LOCATING_TIMEOUT = mParser.getLong(KEY_LOCATING_TIMEOUT,!DEBUG ? 30 * 1000L : 15 * 1000L);LOCATION_ACCURACY = mParser.getFloat(KEY_LOCATION_ACCURACY, 20);// 10 分钟 或者 60 秒MOTION_INACTIVE_TIMEOUT = mParser.getLong(KEY_MOTION_INACTIVE_TIMEOUT,!COMPRESS_TIME ? 10 * 60 * 1000L : 60 * 1000L);long idleAfterInactiveTimeout = (mHasWatch ? 15 : 30) * 60 * 1000L;// 30 分钟 或者 3 分钟IDLE_AFTER_INACTIVE_TIMEOUT = mParser.getLong(KEY_IDLE_AFTER_INACTIVE_TIMEOUT,!COMPRESS_TIME ? idleAfterInactiveTimeout: (idleAfterInactiveTimeout / 10));// 5 分钟 或者 30 秒IDLE_PENDING_TIMEOUT = mParser.getLong(KEY_IDLE_PENDING_TIMEOUT,!COMPRESS_TIME ? 5 * 60 * 1000L : 30 * 1000L);// 10 分钟 或者 60 秒MAX_IDLE_PENDING_TIMEOUT = mParser.getLong(KEY_MAX_IDLE_PENDING_TIMEOUT,!COMPRESS_TIME ? 10 * 60 * 1000L : 60 * 1000L);IDLE_PENDING_FACTOR = mParser.getFloat(KEY_IDLE_PENDING_FACTOR,2f);// 60 分钟 或者 6 分钟IDLE_TIMEOUT = mParser.getLong(KEY_IDLE_TIMEOUT,!COMPRESS_TIME ? 60 * 60 * 1000L : 6 * 60 * 1000L);// 60 小时 或者 30 分钟MAX_IDLE_TIMEOUT = mParser.getLong(KEY_MAX_IDLE_TIMEOUT,!COMPRESS_TIME ? 6 * 60 * 60 * 1000L : 30 * 60 * 1000L);IDLE_FACTOR = mParser.getFloat(KEY_IDLE_FACTOR,2f);// 60 分钟 或者 6 分钟MIN_TIME_TO_ALARM = mParser.getLong(KEY_MIN_TIME_TO_ALARM,!COMPRESS_TIME ? 60 * 60 * 1000L : 6 * 60 * 1000L);MAX_TEMP_APP_WHITELIST_DURATION = mParser.getLong(KEY_MAX_TEMP_APP_WHITELIST_DURATION, 5 * 60 * 1000L);MMS_TEMP_APP_WHITELIST_DURATION = mParser.getLong(KEY_MMS_TEMP_APP_WHITELIST_DURATION, 60 * 1000L);SMS_TEMP_APP_WHITELIST_DURATION = mParser.getLong(KEY_SMS_TEMP_APP_WHITELIST_DURATION, 20 * 1000L);NOTIFICATION_WHITELIST_DURATION = mParser.getLong(KEY_NOTIFICATION_WHITELIST_DURATION, 30 * 1000L);}}
状态变化
我截取的日志，只有以下状态
ACTIVE
INACTIVE
IDLE：doze 省电模式，应用的特性将受到抑制
IDLE_MAINTENANCE:应用窗口期，间隔退出doze模式让应用数据刷新
STATE_ACTIVE
以下任一条件
1.Motion传感器检测到运动或者未知状态
2.Voice-search事件触发
3.亮屏
4.充电
5.命令行 disable
Motion传感器检测到运动或者未知状态
/** Device is currently active. */private static final int STATE_ACTIVE = 0;void handleMotionDetectedLocked(long timeout, String type) {....mState = STATE_ACTIVE;...}亮屏或亮屏
void becomeActiveLocked(String activeReason, int activeUid) {....mState = STATE_ACTIVE;...}查看调用关系void exitForceIdleLocked() {if (mForceIdle) {mForceIdle = false;if (mScreenOn || mCharging) {becomeActiveLocked("exit-force", Process.myUid());}}}void updateDisplayLocked() {mCurDisplay = mDisplayManager.getDisplay(Display.DEFAULT_DISPLAY);// We consider any situation where the display is showing something to be it on,// because if there is anything shown we are going to be updating it at some// frequency so can't be allowed to go into deep sleeps.boolean screenOn = mCurDisplay.getState() == Display.STATE_ON;if (DEBUG) Slog.d(TAG, "updateDisplayLocked: screenOn=" + screenOn);if (!screenOn && mScreenOn) {mScreenOn = false;if (!mForceIdle) {becomeInactiveIfAppropriateLocked();}} else if (screenOn) {mScreenOn = true;if (!mForceIdle) {becomeActiveLocked("screen", Process.myUid());}}}void updateChargingLocked(boolean charging) {if (DEBUG) Slog.i(TAG, "updateChargingLocked: charging=" + charging);if (!charging && mCharging) {mCharging = false;if (!mForceIdle) {becomeInactiveIfAppropriateLocked();}} else if (charging) {mCharging = charging;if (!mForceIdle) {becomeActiveLocked("charging", Process.myUid());}}}命令行 disable
void becomeActiveLocked(String activeReason, int activeUid) {....mState = STATE_ACTIVE;...}查看调用关系if (becomeActive) {becomeActiveLocked((arg == null ? "all" : arg) + "-disabled",Process.myUid());}Voice-search
public void exitIdleInternal(String reason) {synchronized (this) {becomeActiveLocked(reason, Binder.getCallingUid());}}@Override public void exitIdle(String reason) {getContext().enforceCallingOrSelfPermission(Manifest.permission.DEVICE_POWER,null);long ident = Binder.clearCallingIdentity();try {exitIdleInternal(reason);} finally {Binder.restoreCallingIdentity(ident);}}SourceInsight的搜索结果，为voice-search
DeviceIdleController.java (base\services\core\java\com\android\server): @Override public void exitIdle(String reason) {
IDeviceIdleController.aidl (base\core\java\android\os): void exitIdle(String reason);
PhoneWindowManager.java (base\services\core\java\com\android\server\policy): dic.exitIdle("voice-search");
PhoneWindowManager.java (base\services\core\java\com\android\server\policy): STATE_ACTIVE to STATE_INACTIVE
同时满足条件：
暗屏，不充电即可
/** Device is inactive (screen off, no motion) and we are waiting to for idle. */private static final int STATE_INACTIVE = 1;void becomeInactiveIfAppropriateLocked() {if (DEBUG) Slog.d(TAG, "becomeInactiveIfAppropriateLocked()");if ((!mScreenOn && !mCharging) || mForceIdle) {// Screen has turned off; we are now going to become inactive and start// waiting to see if we will ultimately go idle.if (mState == STATE_ACTIVE && mDeepEnabled) {mState = STATE_INACTIVE;if (DEBUG) Slog.d(TAG, "Moved from STATE_ACTIVE to STATE_INACTIVE");resetIdleManagementLocked();scheduleAlarmLocked(mInactiveTimeout, false);EventLogTags.writeDeviceIdle(mState, "no activity");}if (mLightState == LIGHT_STATE_ACTIVE && mLightEnabled) {mLightState = LIGHT_STATE_INACTIVE;if (DEBUG) Slog.d(TAG, "Moved from LIGHT_STATE_ACTIVE to LIGHT_STATE_INACTIVE");resetLightIdleManagementLocked();scheduleLightAlarmLocked(mConstants.LIGHT_IDLE_AFTER_INACTIVE_TIMEOUT);EventLogTags.writeDeviceIdleLight(mLightState, "no activity");}}}// 查看时间mInactiveTimeout = mConstants.INACTIVE_TIMEOUT;// mHasWatch == false,即 30 分钟 或者 3分钟long inactiveTimeoutDefault = (mHasWatch ? 15 : 30) * 60 * 1000L;INACTIVE_TIMEOUT = mParser.getLong(KEY_INACTIVE_TIMEOUT,!COMPRESS_TIME ? inactiveTimeoutDefault : (inactiveTimeoutDefault / 10));Moved to LIGHT_STATE_IDLE
该模式下应用特性会被限制
日志
3,994: 11-17 10:26:25.017778 900 1037 D DeviceIdleController: Moved to LIGHT_STATE_IDLE.
===============================================================
/** Device is in the light idle state, trying to stay asleep as much as possible. */
// private static final int LIGHT_STATE_IDLE = 4;===============================================================
case LIGHT_STATE_IDLE: return "IDLE";case LIGHT_STATE_PRE_IDLE:case LIGHT_STATE_IDLE_MAINTENANCE:if (mMaintenanceStartTime != 0) {long duration = SystemClock.elapsedRealtime() - mMaintenanceStartTime;if (duration < mConstants.LIGHT_IDLE_MAINTENANCE_MIN_BUDGET) {// We didn't use up all of our minimum budget; add this to the reserve.mCurIdleBudget += (mConstants.LIGHT_IDLE_MAINTENANCE_MIN_BUDGET-duration);} else {// We used more than our minimum budget; this comes out of the reserve.mCurIdleBudget -= (duration-mConstants.LIGHT_IDLE_MAINTENANCE_MIN_BUDGET);}}mMaintenanceStartTime = 0;scheduleLightAlarmLocked(mNextLightIdleDelay);mNextLightIdleDelay = Math.min(mConstants.LIGHT_MAX_IDLE_TIMEOUT,(long)(mNextLightIdleDelay * mConstants.LIGHT_IDLE_FACTOR));if (mNextLightIdleDelay < mConstants.LIGHT_IDLE_TIMEOUT) {mNextLightIdleDelay = mConstants.LIGHT_IDLE_TIMEOUT;}if (DEBUG) Slog.d(TAG, "Moved to LIGHT_STATE_IDLE.");mLightState = LIGHT_STATE_IDLE;EventLogTags.writeDeviceIdleLight(mLightState, reason);addEvent(EVENT_LIGHT_IDLE);mGoingIdleWakeLock.acquire();mHandler.sendEmptyMessage(MSG_REPORT_IDLE_ON_LIGHT);break;===============================================================/** Device is about to go idle for the first time, wait for current work to complete. */private static final int LIGHT_STATE_PRE_IDLE = 3;/** Device is in the light idle state, but temporarily out of idle to do regular maintenance. */private static final int LIGHT_STATE_IDLE_MAINTENANCE = 6;=============================================================== LIGHT_PRE_IDLE_TIMEOUT = mParser.getLong(KEY_LIGHT_PRE_IDLE_TIMEOUT,!COMPRESS_TIME ? 10 * 60 * 1000L : 30 * 1000L);Moved to LIGHT_WAITING_FOR_NETWORK 本质还是IDLE
4,793: 11-17 10:26:41.018638 900 1037 D DeviceIdleController: Moved to LIGHT_WAITING_FOR_NETWORK.
===============================================================case LIGHT_STATE_IDLE:case LIGHT_STATE_WAITING_FOR_NETWORK:if (mNetworkConnected || mLightState == LIGHT_STATE_WAITING_FOR_NETWORK) {// We have been idling long enough, now it is time to do some work...........} else {// We'd like to do maintenance, but currently don't have network// connectivity... let's try to wait until the network comes back.// We'll only wait for another full idle period, however, and then give up.scheduleLightAlarmLocked(mNextLightIdleDelay);if (DEBUG) Slog.d(TAG, "Moved to LIGHT_WAITING_FOR_NETWORK.");mLightState = LIGHT_STATE_WAITING_FOR_NETWORK;EventLogTags.writeDeviceIdleLight(mLightState, reason);}break;
===============================================================/** Device is in the light idle state, trying to stay asleep as much as possible. */private static final int LIGHT_STATE_IDLE = 4;/** Device is in the light idle state, we want to go in to idle maintenance but are* waiting for network connectivity before doing so. */private static final int LIGHT_STATE_WAITING_FOR_NETWORK = 5;
LIGHT_STATE_IDLE to LIGHT_STATE_IDLE_MAINTENANCE
case LIGHT_STATE_IDLE:case LIGHT_STATE_WAITING_FOR_NETWORK:if (mNetworkConnected || mLightState == LIGHT_STATE_WAITING_FOR_NETWORK) {// We have been idling long enough, now it is time to do some work.mActiveIdleOpCount = 1;mActiveIdleWakeLock.acquire();mMaintenanceStartTime = SystemClock.elapsedRealtime();if (mCurIdleBudget < mConstants.LIGHT_IDLE_MAINTENANCE_MIN_BUDGET) {mCurIdleBudget = mConstants.LIGHT_IDLE_MAINTENANCE_MIN_BUDGET;} else if (mCurIdleBudget > mConstants.LIGHT_IDLE_MAINTENANCE_MAX_BUDGET) {mCurIdleBudget = mConstants.LIGHT_IDLE_MAINTENANCE_MAX_BUDGET;}scheduleLightAlarmLocked(mCurIdleBudget);if (DEBUG) Slog.d(TAG,"Moved from LIGHT_STATE_IDLE to LIGHT_STATE_IDLE_MAINTENANCE.");mLightState = LIGHT_STATE_IDLE_MAINTENANCE;EventLogTags.writeDeviceIdleLight(mLightState, reason);addEvent(EVENT_LIGHT_MAINTENANCE);mHandler.sendEmptyMessage(MSG_REPORT_IDLE_OFF);Doze模式的完整状态转换
具体解释看源码
void stepIdleStateLocked(String reason) {if (DEBUG) Slog.d(TAG, "stepIdleStateLocked: mState=" + mState);EventLogTags.writeDeviceIdleStep();final long now = SystemClock.elapsedRealtime();if ((now+mConstants.MIN_TIME_TO_ALARM) > mAlarmManager.getNextWakeFromIdleTime()) {// Whoops, there is an upcoming alarm. We don't actually want to go idle.if (mState != STATE_ACTIVE) {becomeActiveLocked("alarm", Process.myUid());becomeInactiveIfAppropriateLocked();}return;}switch (mState) {case STATE_INACTIVE:// We have now been inactive long enough, it is time to start looking// for motion and sleep some more while doing so.startMonitoringMotionLocked();// 运动检测// 5 分钟scheduleAlarmLocked(mConstants.IDLE_AFTER_INACTIVE_TIMEOUT, false);// Reset the upcoming idle delays.// 30 分钟mNextIdlePendingDelay = mConstants.IDLE_PENDING_TIMEOUT;mNextIdleDelay = mConstants.IDLE_TIMEOUT;// 切换当前状态为STATE_IDLE_PENDINGmState = STATE_IDLE_PENDING;if (DEBUG) Slog.d(TAG, "Moved from STATE_INACTIVE to STATE_IDLE_PENDING.");EventLogTags.writeDeviceIdle(mState, reason);break;case STATE_IDLE_PENDING:// 切换当前状态为STATE_SENSING// IDLE_PENDING_TIMEOUT 30 分钟后才可以到这个条件哦mState = STATE_SENSING;if (DEBUG) Slog.d(TAG, "Moved from STATE_IDLE_PENDING to STATE_SENSING.");EventLogTags.writeDeviceIdle(mState, reason);// 4 分钟scheduleSensingTimeoutAlarmLocked(mConstants.SENSING_TIMEOUT);cancelLocatingLocked();mNotMoving = false;mLocated = false;mLastGenericLocation = null;mLastGpsLocation = null;mAnyMotionDetector.checkForAnyMotion();break;case STATE_SENSING:cancelSensingTimeoutAlarmLocked();// 切换当前状态为STATE_LOCATING// 不移动且达到 IDLE_AFTER_INACTIVE_TIMEOUT 5 分钟才可以到这个条件哦mState = STATE_LOCATING;if (DEBUG) Slog.d(TAG, "Moved from STATE_SENSING to STATE_LOCATING.");EventLogTags.writeDeviceIdle(mState, reason);// 30 秒scheduleAlarmLocked(mConstants.LOCATING_TIMEOUT, false);if (mLocationManager != null&& mLocationManager.getProvider(LocationManager.NETWORK_PROVIDER) != null) {mLocationManager.requestLocationUpdates(mLocationRequest,mGenericLocationListener, mHandler.getLooper());mLocating = true;} else {mHasNetworkLocation = false;}if (mLocationManager != null&& mLocationManager.getProvider(LocationManager.GPS_PROVIDER) != null) {mHasGps = true;mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 5,mGpsLocationListener, mHandler.getLooper());mLocating = true;} else {mHasGps = false;}// If we have a location provider, we're all set, the listeners will move state// forward.if (mLocating) {break;}// Otherwise, we have to move from locating into idle maintenance.case STATE_LOCATING:// 切换当前状态为STATE_LOCATING// 角度无改变持续且4分钟才可以到这个状态cancelAlarmLocked();cancelLocatingLocked();mAnyMotionDetector.stop();case STATE_IDLE_MAINTENANCE:// 切换当前状态为STATE_IDLE_MAINTENANCE// GPS无变化且30秒才可以到这个状态scheduleAlarmLocked(mNextIdleDelay, true);if (DEBUG) Slog.d(TAG, "Moved to STATE_IDLE. Next alarm in " + mNextIdleDelay +" ms.");mNextIdleDelay = (long)(mNextIdleDelay * mConstants.IDLE_FACTOR);if (DEBUG) Slog.d(TAG, "Setting mNextIdleDelay = " + mNextIdleDelay);mNextIdleDelay = Math.min(mNextIdleDelay, mConstants.MAX_IDLE_TIMEOUT);if (mNextIdleDelay < mConstants.IDLE_TIMEOUT) {mNextIdleDelay = mConstants.IDLE_TIMEOUT;}mState = STATE_IDLE;if (mLightState != LIGHT_STATE_OVERRIDE) {mLightState = LIGHT_STATE_OVERRIDE;cancelLightAlarmLocked();}EventLogTags.writeDeviceIdle(mState, reason);addEvent(EVENT_DEEP_IDLE);mGoingIdleWakeLock.acquire();mHandler.sendEmptyMessage(MSG_REPORT_IDLE_ON);break;case STATE_IDLE:// 系统会在这个两个状态下（STATE_IDLE与STATE_IDLE_MAINTENANCE）进行交替切换// We have been idling long enough, now it is time to do some work.mActiveIdleOpCount = 1;mActiveIdleWakeLock.acquire();scheduleAlarmLocked(mNextIdlePendingDelay, false);if (DEBUG) Slog.d(TAG, "Moved from STATE_IDLE to STATE_IDLE_MAINTENANCE. " +"Next alarm in " + mNextIdlePendingDelay + " ms.");mMaintenanceStartTime = SystemClock.elapsedRealtime();mNextIdlePendingDelay = Math.min(mConstants.MAX_IDLE_PENDING_TIMEOUT,(long)(mNextIdlePendingDelay * mConstants.IDLE_PENDING_FACTOR));if (mNextIdlePendingDelay < mConstants.IDLE_PENDING_TIMEOUT) {mNextIdlePendingDelay = mConstants.IDLE_PENDING_TIMEOUT;}mState = STATE_IDLE_MAINTENANCE;EventLogTags.writeDeviceIdle(mState, reason);addEvent(EVENT_DEEP_MAINTENANCE);mHandler.sendEmptyMessage(MSG_REPORT_IDLE_OFF);break;}}
结语
Doze模式的省电效果毋庸置疑，我们关注这个模式切换的好处，就是能否借鉴这个思路，进行精确的空闲模式识别。新增一些静默重启的操作，来解决android 系统过于内存碎片化，或者准确识别夜间模式，而不是通过时间进行考量。
