一：什麼是ANR
ANR:Application Not Responding，即應用無響應
二：ANR的類型
ANR一般有三種類型：
1：KeyDispatchTimeout(5 seconds) --主要類型
按鍵或觸摸事件在特定時間內無響應
2：BroadcastTimeout(10 seconds)
BroadcastReceiver在特定時間內無法處理完成
3：ServiceTimeout(20 seconds) --小概率類型
Service在特定的時間內無法處理完成
三：KeyDispatchTimeout
Akey or touch event was not dispatched within the specified time（按鍵或觸摸事件在特定時間內無響應）
具體的超時時間的定義在framework下的
ActivityManagerService.java
//How long we wait until we timeout on key dispatching.
staticfinal int KEY_DISPATCHING_TIMEOUT = 5*1000
四：爲什麼會超時呢？
超時時間的計數一般是從按鍵分發給app開始。超時的原因一般有兩種：
(1)當前的事件沒有機會得到處理（即UI線程正在處理前一個事件，沒有及時的完成或者looper被某種原因阻塞住了）
(2)當前的事件正在處理，但沒有及時完成
五：如何避免KeyDispatchTimeout
1：UI線程儘量只做跟UI相關的工作
2：耗時的工作（比如數據庫操作，I/O，連接網絡或者別的有可能阻礙UI線程的操作）把它放入單獨的線程處理
3：儘量用Handler來處理UIthread和別的thread之間的交互
六：UI線程
說了那麼多的UI線程，那麼哪些屬於UI線程呢？
UI線程主要包括如下：
``` Activity:onCreate(), onResume(), onDestroy(), onKeyDown(), onClick(),etc
AsyncTask: onPreExecute(), onProgressUpdate(), onPostExecute(), onCancel,etc
Mainthread handler: handleMessage(), post*(runnable r), etc
other
七:如何去分析ANR
先看個LOG:
04-01 13:12:11.572 I/InputDispatcher( 220): Application is not responding:Window{2b263310com.android.email/com.android.email.activity.SplitScreenActivitypaused=false}. 5009.8ms since event, 5009.5ms since waitstarted
04-0113:12:11.572 I/WindowManager( 220): Input event dispatching timedout sending tocom.android.email/com.android.email.activity.SplitScreenActivity
04-01 13:12:14.123 I/Process( 220): Sending signal. PID: 21404 SIG: 3---發生ANR的時間和生成trace.txt的時間
04-01 13:12:14.123 I/dalvikvm(21404):threadid=4: reacting to signal 3
……
04-0113:12:15.872 E/ActivityManager( 220): ANR in com.android.email(com.android.email/.activity.SplitScreenActivity)
04-0113:12:15.872 E/ActivityManager( 220): Reason:keyDispatchingTimedOut
04-0113:12:15.872 E/ActivityManager( 220): Load: 8.68 / 8.37 / 8.53
04-0113:12:15.872 E/ActivityManager( 220): CPUusage from 4361ms to 699ms ago ----CPU在ANR發生前的使用情況
04-0113:12:15.872 E/ActivityManager( 220): 5.5%21404/com.android.email: 1.3% user + 4.1% kernel / faults: 10 minor
04-0113:12:15.872 E/ActivityManager( 220): 4.3%220/system_server: 2.7% user + 1.5% kernel / faults: 11 minor 2 major
04-0113:12:15.872 E/ActivityManager( 220): 0.9%52/spi_qsd.0: 0% user + 0.9% kernel
04-0113:12:15.872 E/ActivityManager( 220): 0.5%65/irq/170-cyttsp-: 0% user + 0.5% kernel
04-0113:12:15.872 E/ActivityManager( 220): 0.5%296/com.android.systemui: 0.5% user + 0% kernel
04-0113:12:15.872 E/ActivityManager( 220): 100%TOTAL: 4.8% user + 7.6% kernel + 87% iowait
04-0113:12:15.872 E/ActivityManager( 220): CPUusage from 3697ms to 4223ms later:-- ANR後CPU的使用量
04-0113:12:15.872 E/ActivityManager( 220): 25%21404/com.android.email: 25% user + 0% kernel / faults: 191 minor
04-0113:12:15.872 E/ActivityManager( 220): 16% 21603/__eas(par.hakan: 16% user + 0% kernel
04-0113:12:15.872 E/ActivityManager( 220): 7.2% 21406/GC: 7.2% user + 0% kernel
04-0113:12:15.872 E/ActivityManager( 220): 1.8% 21409/Compiler: 1.8% user + 0% kernel
04-0113:12:15.872 E/ActivityManager( 220): 5.5%220/system_server: 0% user + 5.5% kernel / faults: 1 minor
04-0113:12:15.872 E/ActivityManager( 220): 5.5% 263/InputDispatcher: 0% user + 5.5% kernel
04-0113:12:15.872 E/ActivityManager( 220): 32%TOTAL: 28% user + 3.7% kernel
從LOG可以看出ANR的類型，CPU的使用情況，如果CPU使用量接近100%，說明當前設備很忙，有可能是CPU飢餓導致了ANR
如果CPU使用量很少，說明主線程被BLOCK了
如果IOwait很高，說明ANR有可能是主線程在進行I/O操作造成的
除了看LOG，解決ANR還得需要trace.txt文件，
如何獲取呢？可以用如下命令獲取
$chmod 777 /data/anr
$rm /data/anr/traces.txt
$ps
$kill -3 PID
adbpull data/anr/traces.txt ./mytraces.txt
從trace.txt文件，看到最多的是如下的信息：
-----pid 21404 at 2011-04-01 13:12:14 -----
Cmdline: com.android.email
DALVIK THREADS:
(mutexes: tll=0tsl=0 tscl=0 ghl=0 hwl=0 hwll=0)
"main" prio=5 tid=1NATIVE
| group="main" sCount=1 dsCount=0obj=0x2aad2248 self=0xcf70
| sysTid=21404 nice=0 sched=0/0cgrp=[fopen-error:2] handle=1876218976
atandroid.os.MessageQueue.nativePollOnce(Native Method)
atandroid.os.MessageQueue.next(MessageQueue.java:119)
atandroid.os.Looper.loop(Looper.java:110)
at android.app.ActivityThread.main(ActivityThread.java:3688)
at java.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:507)
atcom.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:624)
at dalvik.system.NativeStart.main(Native Method)
說明主線程在等待下條消息進入消息隊列
八：Thread狀態
[java] view plaincopyprint?
ThreadState (defined at “dalvik/vm/thread.h “)
THREAD_UNDEFINED = -1, /* makes enum compatible with int32_t */
THREAD_ZOMBIE = 0, /* TERMINATED */
THREAD_RUNNING = 1, /* RUNNABLE or running now */
THREAD_TIMED_WAIT = 2, /* TIMED_WAITING in Object.wait() */
THREAD_MONITOR = 3, /* BLOCKED on a monitor */
THREAD_WAIT = 4, /* WAITING in Object.wait() */
THREAD_INITIALIZING= 5, /* allocated, not yet running */
THREAD_STARTING = 6, /* started, not yet on thread list */
THREAD_NATIVE = 7, /* off in a JNI native method */
THREAD_VMWAIT = 8, /* waiting on a VM resource */
THREAD_SUSPENDED = 9, /* suspended, usually by GC or debugger */
九：如何調查並解決ANR
1：首先分析log
2: 從trace.txt文件查看調用stack.
3: 看代碼
4：仔細查看ANR的成因（iowait?block?memoryleak?）
十：案例
案例1：關鍵詞:ContentResolver in AsyncTask onPostExecute, high iowait
Process:com.android.email
Activity:com.android.email/.activity.MessageView
Subject:keyDispatchingTimedOut
CPU usage from 2550ms to -2814ms ago:
5%187/system_server: 3.5% user + 1.4% kernel / faults: 86 minor 20major
4.4% 1134/com.android.email: 0.7% user + 3.7% kernel /faults: 38 minor 19 major
4% 372/com.android.eventstream: 0.7%user + 3.3% kernel / faults: 6 minor
1.1% 272/com.android.phone:0.9% user + 0.1% kernel / faults: 33 minor
0.9%252/com.android.systemui: 0.9% user + 0% kernel
0%409/com.android.eventstream.telephonyplugin: 0% user + 0% kernel /faults: 2 minor
0.1% 632/com.android.devicemonitor: 0.1% user + 0%kernel
100%TOTAL: 6.9% user + 8.2% kernel +84%iowait
-----pid 1134 at 2010-12-17 17:46:51 -----
Cmd line:com.android.email
DALVIK THREADS:
(mutexes: tll=0 tsl=0tscl=0 ghl=0 hwl=0 hwll=0)
"main" prio=5 tid=1 WAIT
|group="main" sCount=1 dsCount=0 obj=0x2aaca180self=0xcf20
| sysTid=1134 nice=0 sched=0/0 cgrp=[fopen-error:2]handle=1876218976
at java.lang.Object.wait(Native Method)
-waiting on <0x2aaca218> (a java.lang.VMThread)
atjava.lang.Thread.parkFor(Thread.java:1424)
atjava.lang.LangAccessImpl.parkFor(LangAccessImpl.java:48)
atsun.misc.Unsafe.park(Unsafe.java:337)
atjava.util.concurrent.locks.LockSupport.park(LockSupport.java:157)
atjava.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:808)
atjava.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:841)
atjava.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1171)
atjava.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:200)
atjava.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:261)
atandroid.database.sqlite.SQLiteDatabase.lock(SQLiteDatabase.java:378)
atandroid.database.sqlite.SQLiteCursor.<init>(SQLiteCursor.java:222)
atandroid.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:53)
atandroid.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1356)
atandroid.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1235)
atandroid.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1189)
atandroid.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1271)
atcom.android.email.provider.EmailProvider.query(EmailProvider.java:1098)
atandroid.content.ContentProvider$Transport.query(ContentProvider.java:187)
atandroid.content.ContentResolver.query(ContentResolver.java:268)
atcom.android.email.provider.EmailContent$Message.restoreMessageWithId(EmailContent.java:648)
atcom.android.email.Controller.setMessageRead(Controller.java:658)
atcom.android.email.activity.MessageView.onMarkAsRead(MessageView.java:700)
atcom.android.email.activity.MessageView.access$2500(MessageView.java:98)
atcom.android.email.activity.MessageView$LoadBodyTask.onPostExecute(MessageView.java:1290)
atcom.android.email.activity.MessageView$LoadBodyTask.onPostExecute(MessageView.java:1255)
atandroid.os.AsyncTask.finish(AsyncTask.java:417)
atandroid.os.AsyncTask.access$300(AsyncTask.java:127)
atandroid.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429)
atandroid.os.Handler.dispatchMessage(Handler.java:99)
atandroid.os.Looper.loop(Looper.java:123)
atandroid.app.ActivityThread.main(ActivityThread.java:3652)
atjava.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:507)
atcom.android.internal.os.ZygoteIn
原因：IOWait很高，說明當前系統在忙於I/O，因此數據庫操作被阻塞
原來：
finalMessagemessage=Message.restoreMessageWithId(mProviderContext,messageId);
if(message==null){
return;
}
Accountaccount=Account.restoreAccountWithId(mProviderContext,message.mAccountKey);
if(account==null){
return;//isMessagingController returns false for null, but let's make itclear.
}
if(isMessagingController(account)){
newThread(){
@Override
publicvoidrun(){
mLegacyController.processPendingActions(message.mAccountKey);
}
}.start();
}
解決後：
newThread() {
finalMessagemessage=Message.restoreMessageWithId(mProviderContext,messageId);
if(message==null){
return;
}
Accountaccount=Account.restoreAccountWithId(mProviderContext,message.mAccountKey);
if(account==null){
return;//isMessagingController returns false for null, but let's make itclear.
}
if(isMessagingController(account)) {
mLegacyController.processPendingActions(message.mAccountKey);
}
}.start();
關於AsyncTask:http://developer.android.com/reference/android/os/AsyncTask.html
案例2：關鍵詞:在UI線程進行網絡數據的讀寫
ANRin process: com.android.mediascape:PhotoViewer (last incom.android.mediascape:PhotoViewer)
Annotation:keyDispatchingTimedOut
CPU usage:
Load: 6.74 / 6.89 / 6.12
CPUusage from 8254ms to 3224ms ago:
ovider.webmedia: 4% = 4% user +0% kernel / faults: 68 minor
system_server: 2% = 1% user + 0%kernel / faults: 18 minor
re-initialized>: 0% = 0% user + 0%kernel / faults: 50 minor
events/0: 0% = 0% user + 0%kernel
TOTAL:7% = 6% user + 1% kernel
DALVIKTHREADS:
""main"" prio=5 tid=3 NATIVE
|group=""main"" sCount=1 dsCount=0 s=Yobj=0x4001b240 self=0xbda8
| sysTid=2579 nice=0 sched=0/0cgrp=unknown handle=-1343993184
atorg.apache.harmony.luni.platform.OSNetworkSystem.receiveStreamImpl(NativeMethod)
atorg.apache.harmony.luni.platform.OSNetworkSystem.receiveStream(OSNetworkSystem.java:478)
atorg.apache.harmony.luni.net.PlainSocketImpl.read(PlainSocketImpl.java:565)
atorg.apache.harmony.luni.net.SocketInputStream.read(SocketInputStream.java:87)
atorg.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnection$LimitedInputStream.read(HttpURLConnection.java:303)
atjava.io.InputStream.read(InputStream.java:133)
atjava.io.BufferedInputStream.fillbuf(BufferedInputStream.java:157)
atjava.io.BufferedInputStream.read(BufferedInputStream.java:346)
atandroid.graphics.BitmapFactory.nativeDecodeStream(Native Method)
atandroid.graphics.BitmapFactory.decodeStream(BitmapFactory.java:459)
atcom.android.mediascape.activity.PhotoViewerActivity.getPreviewImage(PhotoViewerActivity.java:4465)
atcom.android.mediascape.activity.PhotoViewerActivity.dispPreview(PhotoViewerActivity.java:4406)
atcom.android.mediascape.activity.PhotoViewerActivity.access$6500(PhotoViewerActivity.java:125)
atcom.android.mediascape.activity.PhotoViewerActivity$33$1.run(PhotoViewerActivity.java:4558)
atandroid.os.Handler.handleCallback(Handler.java:587)
atandroid.os.Handler.dispatchMessage(Handler.java:92)
atandroid.os.Looper.loop(Looper.java:123)
atandroid.app.ActivityThread.main(ActivityThread.java:4370)
atjava.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:521)
atcom.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
atcom.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
atdalvik.system.NativeStart.main(Native Method)
關於網絡連接，再設計的時候可以設置個timeout的時間或者放入獨立的線程來處理。
關於Handler的問題，可以參考：http://developer.android.com/reference/android/os/Handler.html
案例3：
關鍵詞：Memoryleak/Thread leak
11-1621:41:42.560 I/ActivityManager( 1190): ANR in process:android.process.acore (last in android.process.acore)
11-1621:41:42.560 I/ActivityManager( 1190): Annotation:keyDispatchingTimedOut
11-16 21:41:42.560 I/ActivityManager(1190): CPU usage:
11-16 21:41:42.560 I/ActivityManager( 1190):Load: 11.5 / 11.1 / 11.09
11-16 21:41:42.560 I/ActivityManager(1190): CPU usage from 9046ms to 4018ms ago:
11-16 21:41:42.560I/ActivityManager( 1190): d.process.acore:98%= 97% user + 0% kernel / faults: 1134 minor
11-16 21:41:42.560I/ActivityManager( 1190): system_server: 0% = 0% user + 0% kernel /faults: 1 minor
11-16 21:41:42.560 I/ActivityManager( 1190): adbd:0% = 0% user + 0% kernel
11-16 21:41:42.560 I/ActivityManager(1190): logcat: 0% = 0% user + 0% kernel
11-16 21:41:42.560I/ActivityManager( 1190): TOTAL:100% = 98% user + 1% kernel
Cmdline: android.process.acore
DALVIK THREADS:
"main"prio=5 tid=3 VMWAIT
|group="main" sCount=1 dsCount=0 s=N obj=0x40026240self=0xbda8
| sysTid=1815 nice=0 sched=0/0 cgrp=unknownhandle=-1344001376
atdalvik.system.VMRuntime.trackExternalAllocation(NativeMethod)
atandroid.graphics.Bitmap.nativeCreate(Native Method)
atandroid.graphics.Bitmap.createBitmap(Bitmap.java:468)
atandroid.view.View.buildDrawingCache(View.java:6324)
atandroid.view.View.getDrawingCache(View.java:6178)
atandroid.view.ViewGroup.drawChild(ViewGroup.java:1541)
……
atcom.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1830)
atandroid.view.ViewRoot.draw(ViewRoot.java:1349)
atandroid.view.ViewRoot.performTraversals(ViewRoot.java:1114)
atandroid.view.ViewRoot.handleMessage(ViewRoot.java:1633)
atandroid.os.Handler.dispatchMessage(Handler.java:99)
atandroid.os.Looper.loop(Looper.java:123)
atandroid.app.ActivityThread.main(ActivityThread.java:4370)
atjava.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:521)
atcom.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
atcom.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
atdalvik.system.NativeStart.main(Native Method)
"Thread-408"prio=5 tid=329 WAIT
|group="main" sCount=1 dsCount=0 s=N obj=0x46910d40self=0xcd0548
| sysTid=10602 nice=0 sched=0/0 cgrp=unknownhandle=15470792
at java.lang.Object.wait(Native Method)
-waiting on <0x468cd420> (a java.lang.Object)
atjava.lang.Object.wait(Object.java:288)
atcom.android.dialer.CallLogContentHelper$UiUpdaterExecutor$1.run(CallLogContentHelper.java:289)
atjava.lang.Thread.run(Thread.java:1096)
分析：
atdalvik.system.VMRuntime.trackExternalAllocation(NativeMethod)內存不足導致block在創建bitmap上
**MEMINFO in pid 1360 [android.process.acore] **
native dalvik other total
size: 17036 23111 N/A 40147
allocated: 16484 20675 N/A 37159
free: 296 2436 N/A 2732
解決：如果機器的內存族，可以修改虛擬機的內存爲36M或更大，不過最好是複查代碼，查看哪些內存沒有釋放
========================================================================================
http://www.eoeandroid.com/forum.php?mod=viewthread&tid=165974
Log的產生大家都知道 ， 大家也都知道通過DDMS來看log ， 但什麼時候會產生log文件呢 ？一般在如下幾種情況會產生log文件 。
1，程序異常退出 ， uncaused exception
2，程序強制關閉 ，Force Closed (簡稱FC)
3，程序無響應 ， Application No Response （簡稱ANR) ， 順便，一般主線程超過5秒麼有處理就會ANR
4，手動生成 。
拿到一個日誌文件，要分成多段來看 。 log文件很長，其中包含十幾個小單元信息，但不要被嚇到 ，事實上他主要由三大塊兒組成 。
1，系統基本信息 ，包括 內存，CPU ，進程隊列 ，虛擬內存 ， 垃圾回收等信息 。------ MEMORY INFO (/proc/meminfo) ------
------ CPU INFO (top -n 1 -d 1 -m 30 -t) ------
------ PROCRANK (procrank) ------
------ VIRTUAL MEMORY STATS (/proc/vmstat) ------
------ VMALLOC INFO (/proc/vmallocinfo) ------
格式如下：
------ MEMORY INFO (/proc/meminfo) ------
MemTotal: 347076 kB
MemFree: 56408 kB
Buffers: 7192 kB
Cached: 104064 kB
SwapCached: 0 kB
Active: 192592 kB
Inactive: 40548 kB
Active(anon): 129040 kB
Inactive(anon): 1104 kB
Active(file): 63552 kB
Inactive(file): 39444 kB
Unevictable: 7112 kB
Mlocked: 0 kB
SwapTotal: 0 kB
SwapFree: 0 kB
Dirty: 44 kB
Writeback: 0 kB
AnonPages: 129028 kB
Mapped: 73728 kB
Shmem: 1148 kB
Slab: 13072 kB
SReclaimable: 4564 kB
SUnreclaim: 8508 kB
KernelStack: 3472 kB
PageTables: 12172 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 173536 kB
Committed_AS: 7394524 kB
VmallocTotal: 319488 kB
VmallocUsed: 90752 kB
VmallocChunk: 181252 kB
2，時間信息 ， 也是我們主要分析的信息 。
------ VMALLOC INFO (/proc/vmallocinfo) ------
------ EVENT INFO (/proc/vmallocinfo) ------
格式如下：
------ SYSTEM LOG (logcat -b system -v time -d *:v) ------
01-15 16:41:43.671 W/PackageManager( 2466): Unknown permission com.wsomacp.permission.PROVIDER in package com.android.mms
01-15 16:41:43.671 I/ActivityManager( 2466): Force stopping package com.android.mms uid=10092
01-15 16:41:43.675 I/UsageStats( 2466): Something wrong here, didn't expect com.sec.android.app.twlauncher to be paused
01-15 16:41:44.108 I/ActivityManager( 2466): Start proc com.sec.android.widgetapp.infoalarm for service com.sec.android.widgetapp.infoalarm/.engine.DataService: pid=20634 uid=10005 gids={3003, 1015, 3002}
01-15 16:41:44.175 W/ActivityManager( 2466): Activity pause timeout for HistoryRecord{48589868 com.sec.android.app.twlauncher/.Launcher}
01-15 16:41:50.864 I/KeyInputQueue( 2466): Input event
01-15 16:41:50.866 D/KeyInputQueue( 2466): screenCaptureKeyFlag setting 0
01-15 16:41:50.882 I/PowerManagerService( 2466): Ulight 0->7|0
01-15 16:41:50.882 I/PowerManagerService( 2466): Setting target 2: cur=0.0 target=70 delta=4.6666665 nominalCurrentValue=0
01-15 16:41:50.882 I/PowerManagerService( 2466): Scheduling light animator!
01-15 16:41:51.706 D/PowerManagerService( 2466): enableLightSensor true
01-15 16:41:51.929 I/KeyInputQueue( 2466): Input event
01-15 16:41:51.933 W/WindowManager( 2466): No focus window, dropping: KeyEvent{action=0 code=26 repeat=0 meta=0 scancode=26 mFlags=9}
3，虛擬機信息 ， 包括進程的，線程的跟蹤信息，這是用來跟蹤進程和線程具體點的好地方 。
------ VM TRACES JUST NOW (/data/anr/traces.txt.bugreport: 2011-01-15 16:49:02) ------
------ VM TRACES AT LAST ANR (/data/anr/traces.txt: 2011-01-15 16:49:02) ------
格式如下 ：
----- pid 21161 at 2011-01-15 16:49:01 -----
Cmd line: com.android.mms
DALVIK THREADS:
"main" prio=5 tid=1 NATIVE
| group="main" sCount=1 dsCount=0 s=N obj=0x4001d8d0 self=0xccc8
| sysTid=21161 nice=0 sched=0/0 cgrp=default handle=-1345017808
| schedstat=( 4151552996 5342265329 10995 )
at android.media.MediaPlayer._reset(Native Method)
at android.media.MediaPlayer.reset(MediaPlayer.java:1218)
at android.widget.VideoView.release(VideoView.java:499)
at android.widget.VideoView.access$2100(VideoView.java:50)
at android.widget.VideoView$6.surfaceDestroyed(VideoView.java:489)
at android.view.SurfaceView.reportSurfaceDestroyed(SurfaceView.java:572)
at android.view.SurfaceView.updateWindow(SurfaceView.java:476)
at android.view.SurfaceView.onWindowVisibilityChanged(SurfaceView.java:206)
at android.view.View.dispatchDetachedFromWindow(View.java:6082)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:1156)
at android.view.ViewGroup.removeAllViewsInLayout(ViewGroup.java:2296)
at android.view.ViewGroup.removeAllViews(ViewGroup.java:2254)
at com.android.mms.ui.SlideView.reset(SlideView.java:687)
at com.android.mms.ui.SlideshowPresenter.presentSlide(SlideshowPresenter.java:189)
at com.android.mms.ui.SlideshowPresenter$3.run(SlideshowPresenter.java:531)
at android.os.Handler.handleCallback(Handler.java:587)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4627)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
at dalvik.system.NativeStart.main(Native Method)
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閒話少說， 我總結了觀察log文件的基本步驟 。 1，如果是ANR問題 ， 則搜索“ANR”關鍵詞 。 快速定位到關鍵事件信息 。
2，如果是ForceClosed 和其它異常退出信息，則搜索"Fatal" 關鍵詞， 快速定位到關鍵事件信息 。
3，定位到關鍵事件信息後 ， 如果信息不夠明確的，再去搜索應用程序包的虛擬機信息 ，查看具體的進程和線程跟蹤的日誌，來定位到代碼 。
用這種方法，出現問題，根本不需要斷點調試 ， 直接定位到問題，屢試不爽 。
下面，我們就開始來分析這個例子的log 。
打開log文件 ， 由於是ANR錯誤，因此搜索"ANR " ， 爲何要加空格呢，你加上和去掉比較一下就知道了 。 可以屏蔽掉不少保存到anr.log文件的無效信息 。
定位到關鍵的事件信息如下：
01-15 16:49:02.433 E/ActivityManager( 2466): ANR in com.android.mms (com.android.mms/.ui.SlideshowActivity)
01-15 16:49:02.433 E/ActivityManager( 2466): Reason: keyDispatchingTimedOut
01-15 16:49:02.433 E/ActivityManager( 2466): Load: 0.6 / 0.61 / 0.42
01-15 16:49:02.433 E/ActivityManager( 2466): CPU usage from 1337225ms to 57ms ago:
01-15 16:49:02.433 E/ActivityManager( 2466): sensorserver_ya: 8% = 0% user + 8% kernel / faults: 40 minor
......
01-15 16:49:02.433 E/ActivityManager( 2466): -com.android.mms: 0% = 0% user + 0% kernel
01-15 16:49:02.433 E/ActivityManager( 2466): -flush-179:8: 0% = 0% user + 0% kernel
01-15 16:49:02.433 E/ActivityManager( 2466): TOTAL: 25% = 10% user + 14% kernel + 0% iowait + 0% irq + 0% softirq
01-15 16:49:02.436 I/ ( 2466): dumpmesg > "/data/log/dumpstate_app_anr.log"
我們用自然語言來描述一下日誌，這也算是一種能力吧 。
01-15 16:49:02.433 E/ActivityManager( 2466): ANR in com.android.mms (com.android.mms/.ui.SlideshowActivity)
翻譯：在16:49分2秒433毫秒的時候 ActivityManager （進程號爲2466) 發生瞭如下錯誤：com.android.mms包下面的.ui.SlideshowActivity 無響應 。
01-15 16:49:02.433 E/ActivityManager( 2466): Reason: keyDispatchingTimedOut
翻譯：原因 ， keyDispatchingTimeOut - 按鍵分配超時
01-15 16:49:02.433 E/ActivityManager( 2466): Load: 0.6 / 0.61 / 0.42
翻譯：5分鐘，10分鐘，15分鐘內的平均負載分別爲：0.6 , 0.61 , 0.42
在這裏我們大概知道問題是什麼了，結合我們之前的操作流程，我們知道問題是在點擊按鈕某時候可能處理不過來按鈕事件，導致超時無響應 。那麼現在似乎已經可以進行工作了 。 我們知道Activity中是通過重載dispatchTouchEvent(MotionEvent ev)來處理點擊屏幕事件 。 然後我們可以順藤摸瓜，一點點分析去查找原因 。 但這樣夠了麼 ？
其實不夠 ， 至少我們不能準確的知道到底問題在哪兒 ， 只是猜測 ，比如這個應用程序中，我就在順藤摸瓜的時候發現了多個IO操作的地方都在主線程中，可能引起問題，但不好判斷到底是哪個 ，所以我們目前掌握的信息還不夠 。
於是我們再分析虛擬機信息 ， 搜索“Dalvik Thread”關鍵詞，快速定位到本應用程序的虛擬機信息日誌，如下：
----- pid 2922 at 2011-01-13 13:51:07 -----
Cmd line: com.android.mms
DALVIK THREADS:
"main" prio=5 tid=1 NATIVE
| group="main" sCount=1 dsCount=0 s=N obj=0x4001d8d0 self=0xccc8
| sysTid=2922 nice=0 sched=0/0 cgrp=default handle=-1345017808
| schedstat=( 3497492306 15312897923 10358 )
at android.media.MediaPlayer._release(Native Method)
at android.media.MediaPlayer.release(MediaPlayer.java:1206)
at android.widget.VideoView.stopPlayback(VideoView.java:196)
at com.android.mms.ui.SlideView.stopVideo(SlideView.java:640)
at com.android.mms.ui.SlideshowPresenter.presentVideo(SlideshowPresenter.java:443)
at com.android.mms.ui.SlideshowPresenter.presentRegionMedia(SlideshowPresenter.java:219)
at com.android.mms.ui.SlideshowPresenter$4.run(SlideshowPresenter.java:516)
at android.os.Handler.handleCallback(Handler.java:587)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4627)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
at dalvik.system.NativeStart.main(Native Method)
"Binder Thread #3" prio=5 tid=11 NATIVE
| group="main" sCount=1 dsCount=0 s=N obj=0x4837f808 self=0x242280
| sysTid=3239 nice=0 sched=0/0 cgrp=default handle=2341032
| schedstat=( 32410506 932842514 164 )
at dalvik.system.NativeStart.run(Native Method)
"AsyncQueryWorker" prio=5 tid=9 WAIT
| group="main" sCount=1 dsCount=0 s=N obj=0x482f4b80 self=0x253e10
| sysTid=3236 nice=0 sched=0/0 cgrp=default handle=2432120
| schedstat=( 3225061 26561350 27 )
at java.lang.Object.wait(Native Method)
- waiting on <0x482f4da8> (a android.os.MessageQueue)
at java.lang.Object.wait(Object.java:288)
at android.os.MessageQueue.next(MessageQueue.java:146)
at android.os.Looper.loop(Looper.java:110)
at android.os.HandlerThread.run(HandlerThread.java:60)
"Thread-9" prio=5 tid=8 WAIT
| group="main" sCount=1 dsCount=0 s=N obj=0x4836e2b0 self=0x25af70
| sysTid=2929 nice=0 sched=0/0 cgrp=default handle=2370896
| schedstat=( 130248 4389035 2 )
at java.lang.Object.wait(Native Method)
- waiting on <0x4836e240> (a java.util.ArrayList)
at java.lang.Object.wait(Object.java:288)
at com.android.mms.data.Contact$ContactsCache$TaskStack$1.run(Contact.java:488)
at java.lang.Thread.run(Thread.java:1096)
"Binder Thread #2" prio=5 tid=7 NATIVE
| group="main" sCount=1 dsCount=0 s=N obj=0x482f8ca0 self=0x130fd0
| sysTid=2928 nice=0 sched=0/0 cgrp=default handle=1215968
| schedstat=( 40610049 1837703846 195 )
at dalvik.system.NativeStart.run(Native Method)
"Binder Thread #1" prio=5 tid=6 NATIVE
| group="main" sCount=1 dsCount=0 s=N obj=0x482f4a78 self=0x128a50
| sysTid=2927 nice=0 sched=0/0 cgrp=default handle=1201352
| schedstat=( 40928066 928867585 190 )
at dalvik.system.NativeStart.run(Native Method)
"Compiler" daemon prio=5 tid=5 VMWAIT
| group="system" sCount=1 dsCount=0 s=N obj=0x482f1348 self=0x118960
| sysTid=2926 nice=0 sched=0/0 cgrp=default handle=1149216
| schedstat=( 753021350 3774113668 6686 )
at dalvik.system.NativeStart.run(Native Method)
"JDWP" daemon prio=5 tid=4 VMWAIT
| group="system" sCount=1 dsCount=0 s=N obj=0x482f12a0 self=0x132940
| sysTid=2925 nice=0 sched=0/0 cgrp=default handle=1255680
| schedstat=( 2827103 29553323 19 )
at dalvik.system.NativeStart.run(Native Method)
"Signal Catcher" daemon prio=5 tid=3 RUNNABLE
| group="system" sCount=0 dsCount=0 s=N obj=0x482f11e8 self=0x135988
| sysTid=2924 nice=0 sched=0/0 cgrp=default handle=1173688
| schedstat=( 11793815 12456169 7 )
at dalvik.system.NativeStart.run(Native Method)
"HeapWorker" daemon prio=5 tid=2 VMWAIT
| group="system" sCount=1 dsCount=0 s=N obj=0x45496028 self=0x135848
| sysTid=2923 nice=0 sched=0/0 cgrp=default handle=1222608
| schedstat=( 79049792 1520840200 95 )
at dalvik.system.NativeStart.run(Native Method)
----- end 2922 -----
每一段都是一個線程 ，當然我們還是看線程號爲1的主線程了。通過分析發現關鍵問題是這樣：
at com.android.mms.ui.SlideshowPresenter$3.run(SlideshowPresenter.java:531)
定位到代碼：
mHandler.post(new Runnable() {
public void run() {
try {
presentRegionMedia(view, (RegionMediaModel) model, dataChanged);
} catch (OMADRMException e) {
Log.e(TAG, e.getMessage(), e);
Toast.makeText(mContext,
mContext.getString(R.string.insufficient_drm_rights),
Toast.LENGTH_SHORT).show();
} catch (IOException e){
Log.e(TAG, e.getMessage(), e);
Toast.makeText(mContext,
mContext.getString(R.string.insufficient_drm_rights),
Toast.LENGTH_SHORT).show();
}
}
很清楚了， Handler.post 方法之後執行時間太長的問題 。 繼續看presentRegionMedia(view, (RegionMediaModel) model, dataChanged);方法 ， 發現最終是調用的framework 中MediaPlayer.stop方法 。
至此，我們的日誌分析算是告一段落 。 可以開始思考解決辦法了