com.android.provision基本介紹

1.com.android.provision ANR

（平台android6  mstar晶片  記憶體1G）

1.從device log看，cpu隻有30占用排除cpu導緻的anr

2.anr類型為input dispatching time out 按鍵無響應

3.從trace看，pid 4618主線程處于空閑狀态，不像程序本身原因導緻的anr

E/ActivityManager( 1817): ANR in com.android.provision (com.android.provision/.DefaultActivity)
E/ActivityManager( 1817): PID: 4618
E/ActivityManager( 1817): Reason: Input dispatching timed out (Waiting because no window has focus but there is a focused application that may eventually add a window when it finishes starting up.)
E/ActivityManager( 1817): Load: 6.39 / 3.99 / 1.64
E/ActivityManager( 1817): CPU usage from 2964ms to -3326ms ago:
E/ActivityManager( 1817):   54% 1817/system_server: 22% user + 32% kernel / faults: 6134 minor 18 major
E/ActivityManager( 1817):   0.2% 1298/debuggerd64: 0% user + 0.1% kernel / faults: 8120 minor 14 major
E/ActivityManager( 1817):   0.1% 1296/debuggerd: 0% user + 0.1% kernel / faults: 5868 minor 7 major
E/ActivityManager( 1817):   4.6% 2100/com.android.systemui: 1.4% user + 3.1% kernel / faults: 1639 minor 2 major
E/ActivityManager( 1817):   3.9% 3073/com.android.bluetooth: 2% user + 1.9% kernel / faults: 1216 minor 5 major
...
E/ActivityManager( 1817): 30% TOTAL: 12% user + 16% kernel + 1.8% iowait  //隻有30cpu占用


----- pid 4618 at 2018-05-28 16:48:35 -----
Cmd line: com.android.provision


"main" prio=5 tid=1 Native
  | group="main" sCount=1 dsCount=0 obj=0x7485cf80 self=0xab4c6f60
  | sysTid=4618 nice=0 cgrp=default sched=0/0 handle=0xf7402b34
  | state=S schedstat=( 0 0 0 ) utm=3 stm=1 core=3 HZ=100
  | stack=0xff690000-0xff692000 stackSize=8MB
  | held mutexes=
  kernel: __switch_to+0x74/0x8c
  kernel: SyS_epoll_wait+0x384/0x47c
  kernel: compat_SyS_epoll_pwait+0x124/0x130
  kernel: cpu_switch_to+0x48/0x4c
  native: #00 pc 00043d94  /system/lib/libc.so (__epoll_pwait+20)
  native: #01 pc 0001955f  /system/lib/libc.so (epoll_pwait+26)
  native: #02 pc 0001956d  /system/lib/libc.so (epoll_wait+6)
  native: #03 pc 00012d6b  /system/lib/libutils.so (_ZN7android6Looper9pollInnerEi+102)
  native: #04 pc 00012feb  /system/lib/libutils.so (_ZN7android6Looper8pollOnceEiPiS1_PPv+130)
  native: #05 pc 00083459  /system/lib/libandroid_runtime.so (_ZN7android18NativeMessageQueue8pollOnceEP7_JNIEnvP8_jobjecti+22)
  native: #06 pc 0018b6b5  /data/dalvik-cache/arm/[email protected]@boot.oat (Java_android_os_MessageQueue_nativePollOnce__JI+96)
  at android.os.MessageQueue.nativePollOnce(Native method)
  at android.os.MessageQueue.next(MessageQueue.java:323)
  at android.os.Looper.loop(Looper.java:135)
  at android.app.ActivityThread.main(ActivityThread.java:5417)
  at java.lang.reflect.Method.invoke!(Native method)
  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:731)
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:621)
           

4.檢視device log主程序幹了啥，搜尋關鍵字4618，發現log隻有從anr開始，無相關程序資訊

5.anr本身沒問題，cpu沒問題，檢視是否為memory導緻，發現有大量lowmemorykiller現象，殺死的adj值不算太低，不過此時systemui的adj值為529，感覺有點不合理。此時剩餘記憶體27848kb + 緩存記憶體195224kb = 200m，不算太低，也不算高

28---16-48-48ler( 1290): Error writing /proc/4010/oom_score_a[  188.373842] lowmemorykiller: Killing 'system:ui' (4726), adj 529,
0528---16-48-48[  188.373842]    to free 27848kB on behalf of 'dropcaches.sh' (4800) because
0528---16-48-48[  188.373842]    cache 195244kB is below limit 80000kB for oom_score_adj 529
0528---16-48-48[  188.373842]    Free memory is 171988kB above reserved, free_cma=126260kB
           

6.感覺像是記憶體低導緻

7.檢視app源碼，發現隻有幾行代碼，都是原生的，沒有啥耗時操作

2.provision介紹

Provision的作用很簡單，就是一個系統初始化引導程式，原生的Android裡面Provision隻做了一件事，就是寫入一個DEVICE_PROVISIONED标記。不過這個标記作用很大，這個标記隻會在系統全新更新（雙清）的時候寫入一次，代表了Android系統更新準備完成，可以正常工作。

<intent-filter android:priority="1">
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.HOME" />
                <category android:name="android.intent.category.DEFAULT" />      

屬于launcher,優先級為1，會比一般launcher先啟動起來

3.代碼介紹

代碼位置:android\packages\apps\Provision

public class DefaultActivity extends Activity {

    @Override
    protected void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        // Add a persistent setting to allow other apps to know the device has been provisioned.
        Settings.Global.putInt(getContentResolver(), Settings.Global.DEVICE_PROVISIONED, 1);
        Settings.Secure.putInt(getContentResolver(), Settings.Secure.USER_SETUP_COMPLETE, 1);

        // remove this activity from the package manager.
        PackageManager pm = getPackageManager();
        ComponentName name = new ComponentName(this, DefaultActivity.class);
        pm.setComponentEnabledSetting(name, PackageManager.COMPONENT_ENABLED_STATE_DISABLED,
                PackageManager.DONT_KILL_APP);

        // terminate the activity.
        finish();
    }
}
           

1.Settings.Global.putInt(getContentResolver(), Settings.Global.DEVICE_PROVISIONED, 1);//代表申請完成，寫檔案位于/data/system/users/0/global.xml,也就是此apk隻在清空資料格式化更新和強刷更新會執行

2.執行完後禁止Provision自己的Activity元件

void setComponentEnabledSetting (ComponentName componentName, int newState, int flags)      

• componentName：元件名稱 
• newState：元件新的狀态，可以設定三個值，分别是如下： 
• 　　不可用狀态：COMPONENT_ENABLED_STATE_DISABLED 
• 　　可用狀态：COMPONENT_ENABLED_STATE_ENABLED 
• 　　預設狀态：COMPONENT_ENABLED_STATE_DEFAULT 
• flags:行為标簽，值可以是DONT_KILL_APP或者0。 0說明殺死包含該元件的app