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　一、现象

龙哥发现，省电进程内存占用率高

这里可以使用Android Studio Memory Usage 查看

Memory Usage    360,408K: Persistent             37,159K: com.android.lava.powersave (pid 1873 / activities)

1.查看方法

　二、分析

1.查看应用的 meminfo 信息

adb shell dumpsys meminfo packagename -d

重点关注 Views 和 Activities 变化，如果有差异，则说明存在内存泄露。

Objects               Views:      293         ViewRootImpl:        2         AppContexts:        9           Activities:        5              Assets:        4        AssetManagers:        2       Local Binders:       32        Proxy Binders:       27       Parcel memory:        3         Parcel count:       12    Death Recipients:        0      OpenSSL Sockets:        0            WebViews:        0

2.查看步骤

这里我不断进入我的应用界面，发现 Activities 的数量和我进入界面的次数保持一致，且是递增的，这里内存泄露了

adb shell dumpsys meminfo com.android.lava.powersave -dC:\Users\fadi.su>adb shell dumpsys meminfo com.android.lava.powersave -dApplications Memory Usage (in Kilobytes):Uptime: 59740597 Realtime: 90131515** MEMINFO in pid 1873 [com.android.lava.powersave] **                   Pss  Private  Private  SwapPss     Heap     Heap     Heap                 Total    Dirty    Clean    Dirty     Size    Alloc     Free                ------   ------   ------   ------   ------   ------   ------  Native Heap     8111     7996       92        0    18432    12289     6142  Dalvik Heap     2526     2444       48        0     7129     4278     2851 Dalvik Other      518      492       24       20        Stack       52       52        0        0       Ashmem       82        4        0        0    Other dev        8        4        4        0     .so mmap     5238      156      428       58    .apk mmap      398        0       20        0    .ttf mmap       40        0        0        0    .dex mmap     1268        0     1268        4    .oat mmap     4790        0      648        0    .art mmap     1501      612      360       69   Other mmap     2162        4      932        0   EGL mtrack     3666     3666        0        0    GL mtrack     7137     7137        0        0      Unknown      594      496       92       70        TOTAL    38312    23063     3916      221    25561    16567     8993 App Summary                       Pss(KB)                        ------           Java Heap:     3416         Native Heap:     7996                Code:     2520               Stack:       52            Graphics:    10803       Private Other:     2192              System:    11333               TOTAL:    38312       TOTAL SWAP PSS:      221 Objects               Views:      293         ViewRootImpl:        2         AppContexts:        9           Activities:        5              Assets:        4        AssetManagers:        2       Local Binders:       32        Proxy Binders:       27       Parcel memory:        3         Parcel count:       12    Death Recipients:        0      OpenSSL Sockets:        0            WebViews:        0 SQL         MEMORY_USED:      613  PAGECACHE_OVERFLOW:      258          MALLOC_SIZE:       62 DATABASES      pgsz     dbsz   Lookaside(b)          cache  Dbname         4       24             57       73/51/10  /data/user/0/com.android.lava.powersave/databases/app_usage.db         4       72             54        32/48/7  /data/user/0/com.android.lava.powersave/databases/lavapowersave.db         4      100             43       406/48/7  /data/user/0/com.android.lava.powersave/databases/night_mode.dbC:\Users\fadi.su>

3.查看具体源码

非静态内部类导致的内存泄露，比如Handler，解决方法是将内部类写成静态内部类，在静态内部类中使用软引用/弱引用持有外部类的实例，eg

private final Handler mHandler = new Handler() {        @Override        public void handleMessage(Message msg) {            switch (msg.what) {                case MSG_UPDATE_SWITCH:                    key_power_save_mode.setChecked(PowerSaveManagerUtil.isLavaPowerSaveMode(LavaPowerSaveManager.this));                    key_super_power_save_mode.setChecked(PowerSaveManagerUtil.isLavaSuperPowerSaveMode(LavaPowerSaveManager.this));                case MSG_UPDATE_CLICKABLE:                    key_power_save_mode.setEnabled(true);                    break;            }        }    };

4.优化

@Override    protected void initValues() {        mHandler = new MyHandler(this);    }    private static class MyHandler extends Handler{
           WeakReference
   
     mActivity;        public MyHandler(LavaPowerSaveManager activity) {            mActivity = new WeakReference
    
     (activity);        }        @Override        public void handleMessage(Message msg) {            LavaPowerSaveManager activity = mActivity.get();            switch (msg.what) {                case MSG_UPDATE_SWITCH:                    activity.key_power_save_mode.setChecked(PowerSaveManagerUtil.isLavaPowerSaveMode(activity));                    activity.key_super_power_save_mode.setChecked(PowerSaveManagerUtil.isLavaSuperPowerSaveMode(activity));                case MSG_UPDATE_CLICKABLE:                    activity.key_power_save_mode.setEnabled(true);                    break;            }        }    }
    
   

5.查看优化后结果

不断进入界面，查看 Activities 的数量变化，并且不在是自增，且随着静置的时间越长，Activities 数值越小。

Objects              Views:      125         ViewRootImpl:        1        AppContexts:        7           Activities:        2             Assets:        5        AssetManagers:        3      Local Binders:       32        Proxy Binders:       26      Parcel memory:        3         Parcel count:       14   Death Recipients:        0      OpenSSL Sockets:        0 Objects              Views:      125         ViewRootImpl:        1        AppContexts:        7           Activities:        2             Assets:        5        AssetManagers:        3      Local Binders:       31        Proxy Binders:       25      Parcel memory:        3         Parcel count:       14   Death Recipients:        0      OpenSSL Sockets:        0           WebViews:        0Objects              Views:       56         ViewRootImpl:        1        AppContexts:        6           Activities:        1             Assets:        5        AssetManagers:        3      Local Binders:       28        Proxy Binders:       23      Parcel memory:        3         Parcel count:       14   Death Recipients:        0      OpenSSL Sockets:        0           WebViews:        0

6.小结

这里进行省电模块的排查，尤其是对非静态内部类导致的内存泄露进行优化。