ANR(Application Not Responding) 应用程序无响应。如果你应用程序在UI线程被阻塞太长时间，就会出现ANR，通常出现ANR，系统会弹出一个提示提示框，让用户知道，该程序正在被阻塞，是否继续等待还是关闭。
出现ANR的一般有以下几种类型：
1:KeyDispatchTimeout（常见）
input事件在5S内没有处理完成发生了ANR。
logcat日志关键字：Input event dispatching timed out
2:BroadcastTimeout
前台Broadcast：onReceiver在10S内没有处理完成发生ANR。
后台Broadcast：onReceiver在60s内没有处理完成发生ANR。
logcat日志关键字：Timeout of broadcast BroadcastRecord
3:ServiceTimeout
前台Service：onCreate，onStart，onBind等生命周期在20s内没有处理完成发生ANR。
后台Service：onCreate，onStart，onBind等生命周期在200s内没有处理完成发生ANR
logcat日志关键字：Timeout executing service
4：ContentProviderTimeout
ContentProvider 在10S内没有处理完成发生ANR。 logcat日志关键字：timeout publishing content providers
1:主线程频繁进行耗时的IO操作：如数据库读写
2:多线程操作的死锁，主线程被block；
3:主线程被Binder 对端block；
4:System Server中WatchDog出现ANR；
5:service binder的连接达到上线无法和和System Server通信
6:系统资源已耗尽（管道、CPU、IO）
我们将一步一步分析ANR,这个过程更加理解如何找到问题、分析问题以及解决问题。
查看mobilelog文件夹下的events_log,从日志中搜索关键字：am_anr，找到出现ANR的时间点、进程PID、ANR类型。
如日志：
复制代码07-20 15:36:36.472 1000 1520 1597 I am_anr : [0,1480,com.xxxx.moblie,952680005,Input dispatching timed out (AppWindowToken{da8f666 token=Token{5501f51 ActivityRecord{15c5c78 u0 com.xxxx.moblie/.ui.MainActivity t3862}}}, Waiting because no window has focus but there is a focused application that may eventually add a window when it finishes starting up.)]
从上面的log我们可以看出： 应用com.xxxx.moblie 在07-20 15:36:36.472时间，发生了一次KeyDispatchTimeout类型的ANR，它的进程号是1480. 把关键的信息整理一下：
ANR时间：07-20 15:36:36.472
进程pid：1480
进程名：com.xxxx.moblie
ANR类型：KeyDispatchTimeout
我们已经知道了发生KeyDispatchTimeout的ANR是因为 input事件在5秒内没有处理完成。那么在这个时间07-20 15:36:36.472 的前5秒，也就是（15:36:30 ~15:36:31）时间段左右程序到底做了什么事情？这个简单，因为我们已经知道pid了，再搜索一下pid = 1480的日志.这些日志表示该进程所运行的轨迹，关键的日志如下：
复制代码07-20 15:36:29.749 10102 1480 1737 D moblie-Application: [Thread:17329] receive an intent from server, action=com.ttt.push.RECEIVE_MESSAGE
07-20 15:36:30.136 10102 1480 1737 D moblie-Application: receiving an empty message, drop
07-20 15:36:35.791 10102 1480 1766 I Adreno : QUALCOMM build : 9c9b012, I92eb381bc9
07-20 15:36:35.791 10102 1480 1766 I Adreno : Build Date : 12/31/17
07-20 15:36:35.791 10102 1480 1766 I Adreno : OpenGL ES Shader Compiler Version: EV031.22.00.01
07-20 15:36:35.791 10102 1480 1766 I Adreno : Local Branch :
07-20 15:36:35.791 10102 1480 1766 I Adreno : Remote Branch : refs/tags/AU_LINUX_ANDROID_LA.UM.6.4.R1.08.00.00.309.049
07-20 15:36:35.791 10102 1480 1766 I Adreno : Remote Branch : NONE
07-20 15:36:35.791 10102 1480 1766 I Adreno : Reconstruct Branch : NOTHING
07-20 15:36:35.826 10102 1480 1766 I vndksupport: sphal namespace is not configured for this process. Loading /vendor/lib64/hw/gralloc.msm8998.so from the current namespace instead.
07-20 15:36:36.682 10102 1480 1480 W ViewRootImpl[MainActivity]: Cancelling event due to no window focus: KeyEvent { action=ACTION_UP, keyCode=KEYCODE_PERIOD, scanCode=0, metaState=0, flags=0x28, repeatCount=0, eventTime=16099429, downTime=16099429, deviceId=-1, source=0x101 }
从上面我们可以知道，在时间 07-20 15:36:29.749 程序收到了一个action消息。
复制代码07-20 15:36:29.749 10102 1480 1737 D moblie-Application: [Thread:17329] receive an intent from server, action=com.ttt.push.RECEIVE_MESSAGE。
原来是应用com.xxxx.moblie 收到了一个推送消息（com.ttt.push.RECEIVE_MESSAGE）导致了阻塞，我们再串联一下目前所获取到的信息：在时间07-20 15:36:29.749 应用com.xxxx.moblie 收到了一下推送信息action=com.ttt.push.RECEIVE_MESSAGE发生阻塞，5秒后发生了KeyDispatchTimeout的ANR。
虽然知道了是怎么开始的，但是具体原因还没有找到，是不是当时CPU很紧张、各路APP再抢占资源？ 我们再看看CPU的信息,。搜索关键字关键字： ANR IN
复制代码07-20 15:36:58.711 1000 1520 1597 E ActivityManager: ANR in com.xxxx.moblie (com.xxxx.moblie/.ui.MainActivity) (进程名)
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: PID: 1480 (进程pid)
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: Reason: Input dispatching timed out (AppWindowToken{da8f666 token=Token{5501f51 ActivityRecord{15c5c78 u0 com.xxxx.moblie/.ui.MainActivity t3862}}}, Waiting because no window has focus but there is a focused application that may eventually add a window when it finishes starting up.)
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: Load: 0.0 / 0.0 / 0.0 (Load表明是1分钟,5分钟,15分钟CPU的负载)
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: CPU usage from 20ms to 20286ms later (2018-07-20 15:36:36.170 to 2018-07-20 15:36:56.436):
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 42% 6774/pressure: 41% user + 1.4% kernel / faults: 168 minor
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 34% 142/kswapd0: 0% user + 34% kernel
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 31% 1520/system_server: 13% user + 18% kernel / faults: 58724 minor 1585 major
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 13% 29901/com.ss.android.article.news: 7.7% user + 6% kernel / faults: 56007 minor 2446 major
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 13% 32638/com.android.quicksearchbox: 9.4% user + 3.8% kernel / faults: 48999 minor 1540 major
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 11% (CPU的使用率)1480/com.xxxx.moblie: 5.2%(用户态的使用率) user + (内核态的使用率) 6.3% kernel / faults: 76401 minor 2422 major
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 8.2% 21000/kworker/u16:12: 0% user + 8.2% kernel
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 0.8% 724/mtd: 0% user + 0.8% kernel / faults: 1561 minor 9 major
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 8% 29704/kworker/u16:8: 0% user + 8% kernel
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 7.9% 24391/kworker/u16:18: 0% user + 7.9% kernel
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 7.1% 30656/kworker/u16:14: 0% user + 7.1% kernel
07-20 15:36:58.711 1000 1520 1597 E ActivityManager: 7.1% 9998/kworker/u16:4: 0% user + 7.1% kernel
我已经在log 中标志了相关的含义。com.xxxx.moblie 占用了11%的CPU，其实这并不算多。现在的手机基本都是多核CPU。假如你的CPU是4核，那么上限是400%，以此类推。
既然不是CPU负载的原因，那么到底是什么原因呢？ 这时就要看我们的终极大杀器——traces.txt。
复制代码"main" prio=5 tid=1 Runnable
| group="main" sCount=0 dsCount=0 obj=0x73bcc7d0 self=0x7f20814c00
| sysTid=20176 nice=-10 cgrp=default sched=0/0 handle=0x7f251349b0
| state=R schedstat=( 0 0 0 ) utm=12 stm=3 core=5 HZ=100
| stack=0x7fdb75e000-0x7fdb760000 stackSize=8MB
| held mutexes= "mutator lock"(shared held)
// java 堆栈调用信息,可以查看调用的关系，定位到具体位置
at ttt.push.InterceptorProxy.addMiuiApplication(InterceptorProxy.java:77)
at ttt.push.InterceptorProxy.create(InterceptorProxy.java:59)
at android.app.Activity.onCreate(Activity.java:1041)
at miui.app.Activity.onCreate(SourceFile:47)
at com.xxxx.moblie.ui.b.onCreate(SourceFile:172)
at com.xxxx.moblie.ui.MainActivity.onCreate(SourceFile:68)
at android.app.Activity.performCreate(Activity.java:7050)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2807)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2929)
at android.app.ActivityThread.-wrap11(ActivityThread.java:-1)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1618)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:171)
at android.app.ActivityThread.main(ActivityThread.java:6699)
at java.lang.reflect.Method.invoke(Native method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:246)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:783)
Java的堆栈信息是我们最关心的，它能够定位到具体位置。从上面的traces,我们可以判断ttt.push.InterceptorProxy.addMiuiApplicationInterceptorProxy.java:77 导致了com.xxxx.moblie发生了ANR。这时候可以对着源码查看，找到出问题，并且解决它。
总结一下这分析流程：首先我们搜索am_anr，找到出现ANR的时间点、进程PID、ANR类型、然后再找搜索PID，找前5秒左右的日志。过滤ANR IN 查看CPU信息，接着查看traces.txt，找到java的堆栈信息定位代码位置，最后查看源码，分析与解决问题。这个过程基本能找到发生ANR的来龙去脉。
一、主线程被其他线程lock，导致死锁
waiting on <0x1cd570> (a android.os.MessageQueue)
复制代码DALVIK THREADS:
"main" prio=5 tid=3 TIMED_WAIT
| group="main" sCount=1 dsCount=0 s=0 obj=0x400143a8
| sysTid=691 nice=0 sched=0/0 handle=-1091117924
at java.lang.Object.wait(Native Method)
- waiting on <0x1cd570> (a android.os.MessageQueue)
at java.lang.Object.wait(Object.java:195)
at android.os.MessageQueue.next(MessageQueue.java:144)
at android.os.Looper.loop(Looper.java:110)
at android.app.ActivityThread.main(ActivityThread.java:3742)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:739)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:497)
at dalvik.system.NativeStart.main(Native Method)
"Binder Thread #3" prio=5 tid=15 NATIVE
| group="main" sCount=1 dsCount=0 s=0 obj=0x434e7758
| sysTid=734 nice=0 sched=0/0 handle=1733632
at dalvik.system.NativeStart.run(Native Method)
"Binder Thread #2" prio=5 tid=13 NATIVE
| group="main" sCount=1 dsCount=0 s=0 obj=0x1cd570
| sysTid=696 nice=0 sched=0/0 handle=1369840
at dalvik.system.NativeStart.run(Native Method)
"Binder Thread #1" prio=5 tid=11 NATIVE
| group="main" sCount=1 dsCount=0 s=0 obj=0x433aca10
| sysTid=695 nice=0 sched=0/0 handle=1367448
at dalvik.system.NativeStart.run(Native Method)
----- end 691 -----
二、主线程做耗时的操作：比如数据库读写。
复制代码"main" prio=5 tid=1 Native
held mutexes=
kernel: (couldn't read /proc/self/task/11003/stack)
native: #00 pc 000492a4 /system/lib/libc.so (nanosleep+12)
native: #01 pc 0002dc21 /system/lib/libc.so (usleep+52)
native: #02 pc 00009cab /system/lib/libsqlite.so (???)
native: #03 pc 00011119 /system/lib/libsqlite.so (???)
native: #04 pc 00016455 /system/lib/libsqlite.so (???)
native: #16 pc 0000fa29 /system/lib/libsqlite.so (???)
native: #17 pc 0000fad7 /system/lib/libsqlite.so (sqlite3_prepare16_v2+14)
native: #18 pc 0007f671 /system/lib/libandroid_runtime.so (???)
native: #19 pc 002b4721 /system/framework/arm/boot-framework.oat (Java_android_database_sqlite_SQLiteConnection_nativePrepareStatement__JLjava_lang_String_2+116)
at android.database.sqlite.SQLiteConnection.setWalModeFromConfiguration(SQLiteConnection.java:294)
at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:215)
at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:808)
locked <0x0db193bf> (a java.lang.Object)
at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:793)
at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:696)
at android.app.ContextImpl.openOrCreateDatabase(ContextImpl.java:690)
at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:299)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:223)
at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:163)
locked <0x045a4a8c> (a com.xxxx.video.common.data.DataBaseHelper)
at com.xxxx.video.common.data.DataBaseORM.<init>(DataBaseORM.java:46)
at com.xxxx.video.common.data.DataBaseORM.getInstance(DataBaseORM.java:53)
locked <0x017095d5> (a java.lang.Class<com.xxxx.video.common.data.DataBaseORM>)
三、binder数据量过大
复制代码07-21 04:43:21.573 1000 1488 12756 E Binder : Unreasonably large binder reply buffer: on android.content.pm.BaseParceledListSlice$1@770c74f calling 1 size 388568 (data: 1, 32, 7274595)
07-21 04:43:21.573 1000 1488 12756 E Binder : android.util.Log$TerribleFailure: Unreasonably large binder reply buffer: on android.content.pm.BaseParceledListSlice$1@770c74f calling 1 size 388568 (data: 1, 32, 7274595)
07-21 04:43:21.607 1000 1488 2951 E Binder : Unreasonably large binder reply buffer: on android.content.pm.BaseParceledListSlice$1@770c74f calling 1 size 211848 (data: 1, 23, 7274595)
07-21 04:43:21.607 1000 1488 2951 E Binder : android.util.Log$TerribleFailure: Unreasonably large binder reply buffer: on android.content.pm.BaseParceledListSlice$1@770c74f calling 1 size 211848 (data: 1, 23, 7274595)
07-21 04:43:21.662 1000 1488 6258 E Binder : Unreasonably large binder reply buffer: on android.content.pm.BaseParceledListSlice$1@770c74f calling 1 size 259300 (data: 1, 33, 7274595)
四、binder 通信失败
复制代码07-21 06:04:35.580 <6>[32837.690321] binder: 1698:2362 transaction failed 29189/-3, size 100-0 line 3042
07-21 06:04:35.594 <6>[32837.704042] binder: 1765:4071 transaction failed 29189/-3, size 76-0 line 3042
07-21 06:04:35.899 <6>[32838.009132] binder: 1765:4067 transaction failed 29189/-3, size 224-8 line 3042
07-21 06:04:36.018 <6>[32838.128903] binder: 1765:2397 transaction failed 29189/-22, size 348-0 line 2916
https://juejin.cn/post/6844903715313303565