【笔记】【从Android Guide温习Android 二】ANR (Application Not Responding)
官方文档连接
http://developer.android.com/training/articles/perf-anr.html
ANR产生条件
-
KeyDispatchTimeout -- 按键或点击屏幕5秒内没反应
-
BroadcastTimeout -- BroadcastReceiver没有在10秒内结束
-
ServiceTimeout -- Service20秒内没有处理完成
Time out
虽然和ANR有关，但是并不是所有的Timeout都会引发ANR
因为解决办法和ANR的相同甚至更多。
可以看一下ActivityManagerService或者ActivityStack的源码，搜一下TIMEOUT,如下。
```
// How long we wait until giving up on the last activity to pause. This
// is short because it directly impacts the responsiveness of starting the
// next activity.
static final int PAUSE_TIMEOUT = 500;
// How long we wait for the activity to tell us it has stopped before
// giving up. This is a good amount of time because we really need this
// from the application in order to get its saved state.
static final int STOP_TIMEOUT = 10*1000;
// How long we wait until giving up on an activity telling us it has
// finished destroying itself.
static final int DESTROY_TIMEOUT = 10*1000;
```
可见Acitivy中Pause,Stop,Destory对处理的时间也是有限制的。
如何避免
- 耗时操作都放到工作线程(Worker Thread or Background Thread)中. 如网络请求，数据库读写，图片缩放
可用特性
-
AsyncTask
注意其生命周期
-
Thread
需设置
Process.setThreadPriority(THREAD_PRIORITY_BACKGROUND)。不要使用一下方法阻塞主线程
Thread.wait() or Thread.sleep() -
IntentService
特别适用于BroadcastReceiver中的耗时操作。
用户体验
100到200ms之间，用户会觉得软件运行缓慢。
分析ANR
下面是ANR的log信息
01-10 10:23:04.838 561-586/? E/ActivityManager﹕ ANR in com.android.memorycleaner:remote, time=3677664
Reason: Executing service com.android.memorycleaner/.service.PushService
Load: 1.13 / 1.26 / 1.3
CPU usage from 8110ms to 65ms ago:
11% 701/com.android.systemui: 4.9% user + 6.5% kernel / faults: 108 minor
4.7% 142/surfaceflinger: 1.6% user + 3% kernel
4.5% 561/system_server: 2.7% user + 1.8% kernel / faults: 611 minor
2.1% 4306/kworker/0:2: 0% user + 2.1% kernel
1.9% 5087/com.tangyu.component: 1.2% user + 0.7% kernel / faults: 135 minor
1.9% 5430/com.tencent.qqlive: 1.2% user + 0.7% kernel / faults: 450 minor
1.1% 5545/com.android.vending: 0.6% user + 0.4% kernel / faults: 1854 minor
1.7% 4598/kworker/0:3: 0% user + 1.7% kernel
1.4% 891/com.htc.launcher: 1.2% user + 0.2% kernel / faults: 28 minor
1.1% 140/netd: 0.9% user + 0.1% kernel / faults: 12 minor
0.7% 152/akmd: 0% user + 0.7% kernel
0.4% 153/ewtzmud: 0% user + 0.4% kernel
0.4% 4538/kworker/u:3: 0% user + 0.4% kernel
0.3% 3785/irq/210-host_sp: 0% user + 0.3% kernel
0.2% 111/mmcqd/0: 0% user + 0.2% kernel
0.2% 143/zygote: 0% user + 0.2% kernel / faults: 59 minor
0.2% 456/adbd: 0% user + 0.2% kernel
0.2% 1089/irq/340-wl12xx: 0% user + 0.2% kernel
0.1% 5143/com.android.memorycleaner: 0% user + 0% kernel / faults: 46 minor
0.1% 145/mediaserver: 0% user + 0.1% kernel
0.1% 507/logcat: 0% user + 0.1% kernel
0% 1110/wpa_supplicant: 0% user + 0% kernel
0.1% 3786/irq/214-host_sp: 0% user + 0.1% kernel
0% 5487/com.htc.dnatransfer: 0% user + 0% kernel / faults: 2 minor
0.1% 5616/com.google.android.gm: 0% user + 0.1% kernel
0.1% 5725/com.android.ss: 0.1% user + 0% kernel / faults: 20 minor
+0% 5747/com.htc.calendar: 0% user + 0% kernel
18% TOTAL: 8.2% user + 9.8% kernel + 0.4% iowait + 0% irq + 0.1% softirq
CPU usage from 1435ms to 1956ms later:
5.7% 561/system_server: 3.8% user + 1.9% kernel / faults: 2 minor
3.8% 586/ActivityManager: 1.9% user + 1.9% kernel
1.2% 142/surfaceflinger: 0% user + 1.2% kernel
1.2% 459/EventThread: 0% user + 1.2% kernel
1.3% 701/com.android.systemui: 1.3% user + 0% kernel
2.7% 701/ndroid.systemui: 1.3% user + 1.3% kernel
3.8% TOTAL: 1.9% user + 1.9% kernel
重点看一下这几点
-
原因：
Reason: Executing service com.android.memorycleaner/.service.PushService
啊，com.android.memorycleaner/.service.PushService这个东西引发了ANR
-
Total信息
-
ANR发生前
18% TOTAL: 8.2% user + 9.8% kernel + 0.4% iowait + 0% irq + 0.1% softirq
-
ANR发生后
3.8% TOTAL: 1.9% user + 1.9% kernel
-
可以抽出几个关键词:
-
CPU
-
若CPU彪到了100%，有可能是CPU饥饿导致了ANR
-
若CPU不多。说明主线程被BLOCK了。
当前为18%.
-
-
PID(进程号) + Package-name(包名)
方便确认是你程序的那个进程异常。
-
IOwait
若IOWait高，说明在主线程有读写操作导致ANR。
-
看上去数值没异常
正如此例子。
这时候就可能是另一种情况引起的ANR -- 主线程中有网络通讯
下面就祭上我们的神器 Trace文件
Traces.txt
-
此文件位于设备中的 /data/anr/traces.txt。
-
vi traces.txt查看文件内容。内容有很多。我们只看开始就可以。如下。
1
2
3 ----- pid 13359 at 2014-01-10 12:33:03 -----
4 Cmd line: com.android.memorycleaner:remote
5
6 DALVIK THREADS:
7 (mutexes: tll=0 tsl=0 tscl=0 ghl=0)
8
9 "main" prio=5 tid=1 NATIVE
10 | group="main" sCount=1 dsCount=0 obj=0x41a42e50 self=0x400f6010
11 | sysTid=13359 nice=0 sched=0/0 cgrp=apps handle=1074345436
12 | state=S schedstat=( 626677000 787645000 1599 ) utm=32 stm=30 core=3
13 #00 pc 000180d0 /system/lib/libc.so (poll+12)
14 #01 pc 00020d73 /system/lib/libjavacore.so
15 #02 pc 0001e690 /system/lib/libdvm.so (dvmPlatformInvoke+112)
16 #03 pc 0005100f /system/lib/libdvm.so (dvmCallJNIMethod(unsigned int const*, JValue*, Method const*, Thread*)+426)
17 #04 pc 00027aa0 /system/lib/libdvm.so
18 #05 pc 0002ce84 /system/lib/libdvm.so (dvmInterpret(Thread*, Method const*, JValue*)+232)
19 #06 pc 000674bf /system/lib/libdvm.so (dvmInvokeMethod(Object*, Method const*, ArrayObject*, ArrayObject*, ClassObject*, bool)+374)
20 #07 pc 0007066f /system/lib/libdvm.so
21 #08 pc 00027aa0 /system/lib/libdvm.so
22 #09 pc 0002ce84 /system/lib/libdvm.so (dvmInterpret(Thread*, Method const*, JValue*)+232)
23 #10 pc 000671a1 /system/lib/libdvm.so (dvmCallMethodV(Thread*, Method const*, Object*, bool, JValue*, std::__va_list)+272)
24 #11 pc 0004d2d7 /system/lib/libdvm.so
25 #12 pc 0004d391 /system/lib/libandroid_runtime.so
26 #13 pc 0004e22d /system/lib/libandroid_runtime.so (android::AndroidRuntime::start(char const*, char const*)+540)
27 #14 pc 00000e67 /system/bin/app_process
28 #15 pc 000128b3 /system/lib/libc.so (__libc_init+38)
29 #16 pc 00000b74 /system/bin/app_process
30 at libcore.io.Posix.poll(Native Method)
31 at libcore.io.BlockGuardOs.poll(BlockGuardOs.java:-1)
32 at libcore.io.IoBridge.isConnected(IoBridge.java:-1)
33 at libcore.io.IoBridge.connectErrno(IoBridge.java:-1)
34 at libcore.io.IoBridge.connect(IoBridge.java:-1)
35 at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:-1)
36 at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:-1)
37 at java.net.Socket.connect(Socket.java:-1)
38 at com.b.a.a.a.<init>((null):-1)
39 at com.b.a.a.b.a((null):-1)
40 at com.b.a.e.a((null):-1)
41 at com.b.a.h.a((null):-1)
42 at com.b.a.h.a((null):-1)
43 at com.b.a.k.a((null):-1)
44 at com.b.a.k.a((null):-1)
45 at com.android.memorycleaner.service.c.<init>((null):-1)
46 at com.android.memorycleaner.service.PushService.m((null):-1)
47 at com.android.memorycleaner.service.PushService.q((null):-1)
48 at com.android.memorycleaner.service.PushService.onStart((null):-1)
49 at android.app.Service.onStartCommand(Service.java:-1)
50 at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:-1)
51 at android.app.ActivityThread.access$1900(ActivityThread.java:-1)
52 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:-1)
53 at android.os.Handler.dispatchMessage(Handler.java:-1)
54 at android.os.Looper.loop(Looper.java:-1)
55 at android.app.ActivityThread.main(ActivityThread.java:-1)
56 at java.lang.reflect.Method.invokeNative(Native Method)
57 at java.lang.reflect.Method.invoke(Method.java:-1)
58 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:-1)
59 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:-1)
60 at dalvik.system.NativeStart.main(Native Method)
这部分内容展现的是引发ANR的线程的调用堆栈信息。有了他我们还怕什么！
显而易见
com.android.memorycleaner.service.c.((null):-1) 之上有很多包名的含义直指网络相关。
虽然看不到com.android.memorycleaner.service 的源码。我们可以推断出是由于网络请求导致的ANR。
总结
-
耗时工作通通放到工作线程去做是避免ANR的万金油
-
出现ANR也不用怕。简单分析就能推断出问题所在。
链接
http://www.360doc.com/content/12/0226/15/7635_189765894.shtml
https://dl.google.com/googleio/2010/android-writing-zippy-android-apps.pdf
【笔记】【从Android Guide温习Android 二】ANR (Application Not Responding)