Android Studio 如何分析错误报告

前面的小节我们介绍了调试布局方面的知识,可以有效的帮助我们解决布局显示异常,本小结我们学习如何获取和分析错误报告。

1. 获取错误报告

错误报告包含设备日志、堆栈轨迹和其他诊断信息,可以帮助我们查找和修复应用中的错误。我们可以通过以下几种方式从设备上获取错误报告。

1.1 从真机设备上获取

如需直接从我们的设备上获取错误报告,请执行以下操作:

  1. 确保已启用开发者选项;

  2. 开发者选项中,点按错误报告

  3. 选择所需的错误报告类型,然后点按报告

    稍后,我们便会收到错误报告已准备就绪的通知。

  4. 要分享错误报告,请点按该通知。

1.2 从 Android 模拟器上获取

在 Android 模拟器中,我们可以使用 Extended controls 窗口中的 Bug report 功能:

  1. 点击模拟器面板中的 More 图标;

  2. Extended controls 窗口中,选择左侧的 Bug report
    此时系统会打开一个屏幕,我们可以在其中查看错误报告详细信息,例如屏幕截图、AVD 配置信息和错误报告日志。我们还可以输入一条包含复制步骤的消息,以便与报告一起保存。

  3. 等待错误报告完成收集,然后点击 Save Report

1.3 使用 adb 命令获取

如果我们只连接了一台设备,则可以使用 adb 获取错误报告,如下所示:

$ adb bugreport D:Reports

Tips:如果没有指定错误报告的路径,则系统会将其保存到本地目录。

如果我们连接了多台设备,则必须使用 -s 选项指定设备。运行以下 adb 命令可获取设备序列号并生成错误报告:

$ adb devices
List of devices attached
emulator-5554      device
8XV7N15C31003476 device

$ adb -s 8XV7N15C31003476 bugreport

2. 错误报告文件内容

默认情况下,错误报告是 ZIP 文件。ZIP 文件名类似 bugreport-BUILD_ID-DATE.zip,它可能会包含多个文件,但最重要的文件是 bugreport-BUILD_ID-DATE.txt。此文件就是错误报告,它包含系统服务 (dumpsys)、错误日志 (dumpstate) 和系统消息日志 (logcat) 的诊断输出。系统消息包括设备抛出错误时的堆栈轨迹,以及从所有应用中使用 Log 类写入的消息。

ZIP 文件中有一个 version.txt 元数据文件,其中包含 Android 版本号,而且启用 systrace 后,ZIP 文件中还会包含 systrace.txt 文件。Systrace 工具可以获取并显示应用进程和其他 Android 系统进程的执行时间,从而帮助分析应用的性能。

dumpstate 工具会将文件从设备的文件系统复制到 ZIP 文件的 FS 文件夹下,以便我们引用它们。例如,设备中的 /dirA/dirB/fileC 文件会在 ZIP 文件中生成 FS/dirA/dirB/fileC 条目

错误报告文件结构如下:

3. 常见日志分析

3.1 ANR 和死锁

错误报告有助于我们找出导致应用无响应 (ANR) 错误和死锁事件的原因。

  • 找出无响应的应用
    当某个应用在一定时间内没有响应(通常是由于主线程被阻塞或繁忙)时,系统会终止该进程并将堆栈转储到 /data/anr。要找出 ANR 背后的罪魁祸首,请为二进制事件日志中的 am_anr 执行 grep 命令。
    日志范例如下:
grep "am_anr" bugreport-2015-10-01-18-13-48.txt
10-01 18:12:49.599  4600  4614 I am_anr  : [0,29761,com.google.android.youtube,953695941,executing service com.google.android.youtube/com.google.android.apps.youtube.app.offline.transfer.OfflineTransferService]
10-01 18:14:10.211  4600  4614 I am_anr  : [0,30363,com.google.android.apps.plus,953728580,executing service com.google.android.apps.plus/com.google.android.apps.photos.service.PhotosService]

我们也可以为 logcat 日志(其中包含关于发生 ANR 时是什么在占用 CPU 的更多信息)中的 ANR in 执行 grep 命令。
日志范例如下:

grep "ANR in" bugreport-2015-10-01-18-13-48.txt
10-01 18:13:11.984  4600  4614 E ActivityManager: ANR in com.google.android.youtube
10-01 18:14:31.720  4600  4614 E ActivityManager: ANR in com.google.android.apps.plus
10-01 18:14:31.720  4600  4614 E ActivityManager: PID: 30363
10-01 18:14:31.720  4600  4614 E ActivityManager: Reason: executing service com.google.android.apps.plus/com.google.android.apps.photos.service.PhotosService
10-01 18:14:31.720  4600  4614 E ActivityManager: Load: 35.27 / 23.9 / 16.18
10-01 18:14:31.720  4600  4614 E ActivityManager: CPU usage from 16ms to 21868ms later:
10-01 18:14:31.720  4600  4614 E ActivityManager:   74% 3361/mm-qcamera-daemon: 62% user + 12% kernel / faults: 15276 minor 10 major
10-01 18:14:31.720  4600  4614 E ActivityManager:   41% 4600/system_server: 18% user + 23% kernel / faults: 18597 minor 309 major
10-01 18:14:31.720  4600  4614 E ActivityManager:   32% 27420/com.google.android.GoogleCamera: 24% user + 7.8% kernel / faults: 48374 minor 338 major
10-01 18:14:31.720  4600  4614 E ActivityManager:   16% 130/kswapd0: 0% user + 16% kernel
10-01 18:14:31.720  4600  4614 E ActivityManager:   15% 283/mmcqd/0: 0% user + 15% kernel
...
10-01 18:14:31.720  4600  4614 E ActivityManager:   0.1% 27248/irq/503-synapti: 0%
10-01 18:14:31.721  4600  4614 I ActivityManager: Killing 30363:com.google.android.apps.plus/u0a206 (adj 0): bg anr
  • 查找堆栈跟踪
    通常我们可以找到与 ANR 对应的堆栈跟踪。请确保 VM 跟踪上的时间戳和 PID 与我们正在调查的 ANR 相符,然后再检查进程的主线程。
    日志范例如下:
VM TRACES AT LAST ANR (/data/anr/traces.txt: 2015-10-01 18:14:41)
pid 30363 at 2015-10-01 18:14:11
Cmd line: com.google.android.apps.plus
Build fingerprint: 'google/angler/angler:6.0/MDA89D/2294819:userdebug/dev-keys'
ABI: 'arm'
Build type: optimized
Zygote loaded classes=3978 post zygote classes=27
Intern table: 45068 strong; 21 weak
JNI: CheckJNI is off; globals=283 (plus 360 weak)
Libraries: /system/lib/libandroid.so /system/lib/libcompiler_rt.so /system/lib/libjavacrypto.so /system/lib/libjnigraphics.so /system/lib/libmedia_jni.so /system/lib/libwebviewchromium_loader.so libjavacore.so (7)
Heap: 29% free, 21MB/30MB; 32251 objects
Dumping cumulative Gc timings
Total number of allocations 32251
Total bytes allocated 21MB
Total bytes freed 0B
Free memory 9MB
Free memory until GC 9MB
Free memory until OOME 490MB
Total memory 30MB
Max memory 512MB
Zygote space size 1260KB
Total mutator paused time: 0
Total time waiting for GC to complete: 0
Total GC count: 0
Total GC time: 0
Total blocking GC count: 0
Total blocking GC time: 0
suspend all histogram:  Sum: 119.728ms 99% C.I. 0.010ms-107.765ms Avg: 5.442ms Max: 119.562ms
DALVIK THREADS (12):
"Signal Catcher" daemon prio=5 tid=2 Runnable
  | group="system" sCount=0 dsCount=0 obj=0x12c400a0 self=0xef460000
  | sysTid=30368 nice=0 cgrp=default sched=0/0 handle=0xf4a69930
  | state=R schedstat=( 9021773 5500523 26 ) utm=0 stm=0 core=1 HZ=100
  | stack=0xf496d000-0xf496f000 stackSize=1014KB
  | held mutexes= "mutator lock"(shared held)
  native: #00 pc 0035a217  /system/lib/libart.so (art::DumpNativeStack(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, int, char const*, art::ArtMethod*, void*)+126)
  native: #01 pc 0033b03b  /system/lib/libart.so (art::Thread::Dump(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) const+138)
  native: #02 pc 00344701  /system/lib/libart.so (art::DumpCheckpoint::Run(art::Thread*)+424)
  native: #03 pc 00345265  /system/lib/libart.so (art::ThreadList::RunCheckpoint(art::Closure*)+200)
  native: #04 pc 00345769  /system/lib/libart.so (art::ThreadList::Dump(std::__1::basic_ostream<char, std::__1::char_traits<char> >&)+124)
  native: #05 pc 00345e51  /system/lib/libart.so (art::ThreadList::DumpForSigQuit(std::__1::basic_ostream<char, std::__1::char_traits<char> >&)+312)
  native: #06 pc 0031f829  /system/lib/libart.so (art::Runtime::DumpForSigQuit(std::__1::basic_ostream<char, std::__1::char_traits<char> >&)+68)
  native: #07 pc 00326831  /system/lib/libart.so (art::SignalCatcher::HandleSigQuit()+896)
  native: #08 pc 003270a1  /system/lib/libart.so (art::SignalCatcher::Run(void*)+324)
  native: #09 pc 0003f813  /system/lib/libc.so (__pthread_start(void*)+30)
  native: #10 pc 00019f75  /system/lib/libc.so (__start_thread+6)
  (no managed stack frames)
"main" prio=5 tid=1 Suspended
  | group="main" sCount=1 dsCount=0 obj=0x747552a0 self=0xf5376500
  | sysTid=30363 nice=0 cgrp=default sched=0/0 handle=0xf74feb34
  | state=S schedstat=( 331107086 164153349 851 ) utm=6 stm=27 core=3 HZ=100
  | stack=0xff00f000-0xff011000 stackSize=8MB
  | held mutexes=
  kernel: __switch_to+0x7c/0x88
  kernel: futex_wait_queue_me+0xd4/0x130
  kernel: futex_wait+0xf0/0x1f4
  kernel: do_futex+0xcc/0x8f4
  kernel: compat_SyS_futex+0xd0/0x14c
  kernel: cpu_switch_to+0x48/0x4c
  native: #00 pc 000175e8  /system/lib/libc.so (syscall+28)
  native: #01 pc 000f5ced  /system/lib/libart.so (art::ConditionVariable::Wait(art::Thread*)+80)
  native: #02 pc 00335353  /system/lib/libart.so (art::Thread::FullSuspendCheck()+838)
  native: #03 pc 0011d3a7  /system/lib/libart.so (art::ClassLinker::LoadClassMembers(art::Thread*, art::DexFile const&, unsigned char const*, art::Handle<art::mirror::Class>, art::OatFile::OatClass const*)+746)
  native: #04 pc 0011d81d  /system/lib/libart.so (art::ClassLinker::LoadClass(art::Thread*, art::DexFile const&, art::DexFile::ClassDef const&, art::Handle<art::mirror::Class>)+88)
  native: #05 pc 00132059  /system/lib/libart.so (art::ClassLinker::DefineClass(art::Thread*, char const*, unsigned int, art::Handle<art::mirror::ClassLoader>, art::DexFile const&, art::DexFile::ClassDef const&)+320)
  native: #06 pc 001326c1  /system/lib/libart.so (art::ClassLinker::FindClassInPathClassLoader(art::ScopedObjectAccessAlreadyRunnable&, art::Thread*, char const*, unsigned int, art::Handle<art::mirror::ClassLoader>, art::mirror::Class**)+688)
  native: #07 pc 002cb1a1  /system/lib/libart.so (art::VMClassLoader_findLoadedClass(_JNIEnv*, _jclass*, _jobject*, _jstring*)+264)
  native: #08 pc 002847fd  /data/dalvik-cache/arm/system@framework@boot.oat (Java_java_lang_VMClassLoader_findLoadedClass__Ljava_lang_ClassLoader_2Ljava_lang_String_2+112)
  at java.lang.VMClassLoader.findLoadedClass!(Native method)
  at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:362)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:499)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
  at android.app.ActivityThread.installProvider(ActivityThread.java:5141)
  at android.app.ActivityThread.installContentProviders(ActivityThread.java:4748)
  at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4688)
  at android.app.ActivityThread.-wrap1(ActivityThread.java:-1)
  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1405)
  at android.os.Handler.dispatchMessage(Handler.java:102)
  at android.os.Looper.loop(Looper.java:148)
  at android.app.ActivityThread.main(ActivityThread.java:5417)
  at java.lang.reflect.Method.invoke!(Native method)
  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
  • 查找死锁
    由于线程出现粘滞,死锁往往首先表现为 ANR。如果系统服务器发生死锁,监控程序最终会将其终止,从而导致日志中出现类似以下的条目:WATCHDOG KILLING SYSTEM PROCESS。对于用户来说,看到的是设备重新启动,但从技术上来讲这是运行时重启,而不是真正的设备重新启动。
    要查找死锁,请检查 VM 跟踪部分中是否存在以下模式:线程 A 在等待线程 B 占用的某些资源,而线程 B 也在等待线程 A 占用的某些资源。
    日志范例如下:
"Binder_B" prio=5 tid=73 Blocked
  | group="main" sCount=1 dsCount=0 obj=0x13faa0a0 self=0x95e24800
  | sysTid=2016 nice=0 cgrp=default sched=0/0 handle=0x8b68d930
  | state=S schedstat=( 9351576559 4141431119 16920 ) utm=819 stm=116 core=1 HZ=100
  | stack=0x8b591000-0x8b593000 stackSize=1014KB
  | held mutexes=
  at com.android.server.pm.UserManagerService.exists(UserManagerService.java:387)
  - waiting to lock <0x025f9b02> (a android.util.ArrayMap) held by thread 20
  at com.android.server.pm.PackageManagerService.getApplicationInfo(PackageManagerService.java:2848)
  at com.android.server.AppOpsService.getOpsRawLocked(AppOpsService.java:881)
  at com.android.server.AppOpsService.getOpsLocked(AppOpsService.java:856)
  at com.android.server.AppOpsService.noteOperationUnchecked(AppOpsService.java:719)
  - locked <0x0231885a> (a com.android.server.AppOpsService)
  at com.android.server.AppOpsService.noteOperation(AppOpsService.java:713)
  at com.android.server.AppOpsService$2.getMountMode(AppOpsService.java:260)
  at com.android.server.MountService$MountServiceInternalImpl.getExternalStorageMountMode(MountService.java:3416)
  at com.android.server.am.ActivityManagerService.startProcessLocked(ActivityManagerService.java:3228)
  at com.android.server.am.ActivityManagerService.startProcessLocked(ActivityManagerService.java:3170)
  at com.android.server.am.ActivityManagerService.startProcessLocked(ActivityManagerService.java:3059)
  at com.android.server.am.BroadcastQueue.processNextBroadcast(BroadcastQueue.java:1070)
  - locked <0x044d166f> (a com.android.server.am.ActivityManagerService)
  at com.android.server.am.ActivityManagerService.finishReceiver(ActivityManagerService.java:16950)
  at android.app.ActivityManagerNative.onTransact(ActivityManagerNative.java:494)
  at com.android.server.am.ActivityManagerService.onTransact(ActivityManagerService.java:2432)
  at android.os.Binder.execTransact(Binder.java:453)
"PackageManager" prio=5 tid=20 Blocked
  | group="main" sCount=1 dsCount=0 obj=0x1304f4a0 self=0xa7f43900
  | sysTid=1300 nice=10 cgrp=bg_non_interactive sched=0/0 handle=0x9fcf9930
  | state=S schedstat=( 26190141996 13612154802 44357 ) utm=2410 stm=209 core=2 HZ=100
  | stack=0x9fbf7000-0x9fbf9000 stackSize=1038KB
  | held mutexes=
  at com.android.server.AppOpsService.noteOperationUnchecked(AppOpsService.java:718)
  - waiting to lock <0x0231885a> (a com.android.server.AppOpsService) held by thread 73
  at com.android.server.AppOpsService.noteOperation(AppOpsService.java:713)
  at com.android.server.AppOpsService$2.getMountMode(AppOpsService.java:260)
  at com.android.server.AppOpsService$2.hasExternalStorage(AppOpsService.java:273)
  at com.android.server.MountService$MountServiceInternalImpl.hasExternalStorage(MountService.java:3431)
  at com.android.server.MountService.getVolumeList(MountService.java:2609)
  at android.os.storage.StorageManager.getVolumeList(StorageManager.java:880)
  at android.os.Environment$UserEnvironment.getExternalDirs(Environment.java:83)
  at android.os.Environment.isExternalStorageEmulated(Environment.java:708)
  at com.android.server.pm.PackageManagerService.isExternalMediaAvailable(PackageManagerService.java:9327)
  at com.android.server.pm.PackageManagerService.startCleaningPackages(PackageManagerService.java:9367)
  - locked <0x025f9b02> (a android.util.ArrayMap)
  at com.android.server.pm.PackageManagerService$PackageHandler.doHandleMessage(PackageManagerService.java:1320)
  at com.android.server.pm.PackageManagerService$PackageHandler.handleMessage(PackageManagerService.java:1122)
  at android.os.Handler.dispatchMessage(Handler.java:102)
  at android.os.Looper.loop(Looper.java:148)
  at android.os.HandlerThread.run(HandlerThread.java:61)
  at com.android.server.ServiceThread.run(ServiceThread.java:46)

3.2 Activity 活动

  • 查看处于聚焦状态的 Activity
    要查看记录的处于聚焦状态的 Activity,请搜索 am_focused_activity。
    日志范例如下:
grep "am_focused_activity" bugreport-2015-10-01-18-13-48.txt
10-01 18:10:41.409  4600 14112 I am_focused_activity: [0,com.google.android.GoogleCamera/com.android.camera.CameraActivity]
10-01 18:11:17.313  4600  5687 I am_focused_activity: [0,com.google.android.googlequicksearchbox/com.google.android.launcher.GEL]
10-01 18:11:52.747  4600 14113 I am_focused_activity: [0,com.google.android.GoogleCamera/com.android.camera.CameraActivity]
10-01 18:14:07.762  4600  5687 I am_focused_activity: [0,com.google.android.googlequicksearchbox/com.google.android.launcher.GEL]
  • 查看进程启动事件
    要查看记录的进程启动事件,请搜索 Start proc。
    日志范例如下:
grep "Start proc" bugreport-2015-10-01-18-13-48.txt
10-01 18:09:15.309  4600  4612 I ActivityManager: Start proc 24533:com.metago.astro/u0a240 for broadcast com.metago.astro/com.inmobi.commons.analytics.androidsdk.IMAdTrackerReceiver
10-01 18:09:15.687  4600 14112 I ActivityManager: Start proc 24548:com.google.android.apps.fitness/u0a173 for service com.google.android.apps.fitness/.api.services.ActivityUpsamplingService
10-01 18:09:15.777  4600  6604 I ActivityManager: Start proc 24563:cloudtv.hdwidgets/u0a145 for broadcast cloudtv.hdwidgets/cloudtv.switches.SwitchSystemUpdateReceiver
10-01 18:09:20.574  4600  6604 I ActivityManager: Start proc 24617:com.wageworks.ezreceipts/u0a111 for broadcast com.wageworks.ezreceipts/.ui.managers.IntentReceiver
  • 设备是否发生系统颠簸
    要确定设备是否发生系统颠簸,请检查 am_proc_died 和 am_proc_start 前后在短时间内是否出现活动异常增加。
    日志范例如下:
grep -e "am_proc_died" -e "am_proc_start" bugreport-2015-10-01-18-13-48.txt
10-01 18:07:06.494  4600  9696 I am_proc_died: [0,20074,com.android.musicfx]
10-01 18:07:06.555  4600  6606 I am_proc_died: [0,31166,com.concur.breeze]
10-01 18:07:06.566  4600 14112 I am_proc_died: [0,18812,com.google.android.apps.fitness]
10-01 18:07:07.018  4600  7513 I am_proc_start: [0,20361,10113,com.sony.playmemories.mobile,broadcast,com.sony.playmemories.mobile/.service.StartupReceiver]
10-01 18:07:07.357  4600  4614 I am_proc_start: [0,20381,10056,com.google.android.talk,service,com.google.android.talk/com.google.android.libraries.hangouts.video.CallService]
10-01 18:07:07.784  4600  4612 I am_proc_start: [0,20402,10190,com.andcreate.app.trafficmonitor:loopback_measure_serivce,service,com.andcreate.app.trafficmonitor/.loopback.LoopbackMeasureService]
10-01 18:07:10.753  4600  5997 I am_proc_start: [0,20450,10097,com.amazon.mShop.android.shopping,broadcast,com.amazon.mShop.android.shopping/com.amazon.identity.auth.device.storage.LambortishClock$ChangeTimestampsBroadcastReceiver]
10-01 18:07:15.267  4600  6605 I am_proc_start: [0,20539,10173,com.google.android.apps.fitness,service,com.google.android.apps.fitness/.api.services.ActivityUpsamplingService]
10-01 18:07:15.985  4600  4612 I am_proc_start: [0,20568,10022,com.android.musicfx,broadcast,com.android.musicfx/.ControlPanelReceiver]
10-01 18:07:16.315  4600  7512 I am_proc_died: [0,20096,com.google.android.GoogleCamera]

3.3 内存异常

内存不足可能会导致系统发生颠簸,这是因为虽然内存不足时系统会终止某些进程来释放内存,但又会继续启动其他进程。要查看内存不足的确凿证据,请检查二进制事件日志中 am_proc_diedam_proc_start 条目的密集程度。

内存不足还可能会减慢任务切换速度,并且可能会阻止进行返回尝试(因为用户尝试返回到的任务已被终止)。如果启动器被终止,它会在用户触摸主屏幕按钮时重启,并且日志中会显示启动器重新加载其内容。

  • 查看历史指标
    二进制事件日志中的 am_low_memory 条目表示最后一个缓存的进程已终止。在此之后,系统开始终止各项服务。
    日志范例如下:
grep "am_low_memory" bugreport-2015-10-01-18-13-48.txt
10-01 18:11:02.219  4600  7513 I am_low_memory: 41
10-01 18:12:18.526  4600 14112 I am_low_memory: 39
10-01 18:12:18.874  4600  7514 I am_low_memory: 38
10-01 18:12:22.570  4600 14112 I am_low_memory: 40
10-01 18:12:34.811  4600 20319 I am_low_memory: 43
10-01 18:12:37.945  4600  6521 I am_low_memory: 43
10-01 18:12:47.804  4600 14110 I am_low_memory: 43
  • 查看系统颠簸指标
    关于系统颠簸(分页、直接回收等)的其他指标包括 kswapd、kworker 和 mmcqd 消耗的 CPU 周期。
    日志范例如下:
CPU INFO (top -n 1 -d 1 -m 30 -t)
User 15%, System 54%, IOW 28%, IRQ 0%
User 82 + Nice 2 + Sys 287 + Idle 1 + IOW 152 + IRQ 0 + SIRQ 5 = 529
  PID   TID PR CPU% S     VSS     RSS PCY UID      Thread          Proc
15229 15229  0  19% R      0K      0K  fg root     kworker/0:2
29512 29517  1   7% D 1173524K 101188K  bg u0_a27   Signal Catcher  com.google.android.talk
24565 24570  3   6% D 2090920K 145168K  fg u0_a22   Signal Catcher  com.google.android.googlequicksearchbox:search
19525 19525  2   6% R   3476K   1644K  fg shell    top             top
24957 24962  2   5% R 1706928K 125716K  bg u0_a47   Signal Catcher  com.google.android.GoogleCamera
19519 19519  3   4% S      0K      0K  fg root     kworker/3:1
  120   120  0   3% S      0K      0K  fg root     mmcqd/1
18233 18233  1   3% S      0K      0K  fg root     kworker/1:1
25589 25594  1   2% D 1270476K  75776K  fg u0_a8    Signal Catcher  com.google.android.gms
19399 19399  2   1% S      0K      0K  fg root     kworker/2:2
 1963  1978  1   0% S 1819100K 125136K  fg system   android.fg      system_server
 1963  1981  3   0% S 1819100K 125136K  fg system   android.display system_server
  • 获取内存快照
    内存快照是一种 dumpstate,其中会列出正在运行的 Java 进程和本机进程.
    日志范例如下:
Total PSS by OOM adjustment:
    86752 kB: Native
               22645 kB: surfaceflinger (pid 197)
               18597 kB: mediaserver (pid 204)
   136959 kB: System
              136959 kB: system (pid 785)
   220218 kB: Persistent
              138859 kB: com.android.systemui (pid 947 / activities)
               39178 kB: com.android.nfc (pid 1636)
               28313 kB: com.android.phone (pid 1659)
               13868 kB: com.redbend.vdmc (pid 1646)
     9534 kB: Persistent Service
                9534 kB: com.android.bluetooth (pid 23807)
   178604 kB: Foreground
              168620 kB: com.google.android.googlequicksearchbox (pid 1675 / activities)
                9984 kB: com.google.android.apps.maps (pid 13952)
   188286 kB: Visible
               85326 kB: com.google.android.wearable.app (pid 1535)
               38978 kB: com.google.process.gapps (pid 1510)
               31936 kB: com.google.android.gms.persistent (pid 2072)
               27950 kB: com.google.android.gms.wearable (pid 1601)
                4096 kB: com.google.android.googlequicksearchbox:interactor (pid 1550)
    52948 kB: Perceptible
               52948 kB: com.google.android.inputmethod.latin (pid 1566)
   150851 kB: A Services
               81121 kB: com.google.android.gms (pid 1814)
               37586 kB: com.google.android.talk (pid 9584)
               10949 kB: com.google.android.music:main (pid 4019)
               10727 kB: com.motorola.targetnotif (pid 31071)
               10468 kB: com.google.android.GoogleCamera (pid 9984)
    33298 kB: Previous
               33298 kB: com.android.settings (pid 9673 / activities)
   165188 kB: B Services
               49490 kB: com.facebook.katana (pid 15035)
               22483 kB: com.whatsapp (pid 28694)
               21308 kB: com.iPass.OpenMobile (pid 5325)
               19788 kB: com.google.android.apps.googlevoice (pid 23934)
               17399 kB: com.google.android.googlequicksearchbox:search (pid 30359)
                9073 kB: com.google.android.apps.youtube.unplugged (pid 21194)
                7660 kB: com.iPass.OpenMobile:remote (pid 23754)
                7291 kB: com.pujie.wristwear.pujieblack (pid 24240)
                7157 kB: com.instagram.android:mqtt (pid 9530)
                3539 kB: com.qualcomm.qcrilmsgtunnel (pid 16186)
   204324 kB: Cached
               43424 kB: com.amazon.mShop.android (pid 13558)
               22563 kB: com.google.android.apps.magazines (pid 13844)
                4298 kB: com.google.android.apps.enterprise.dmagent (pid 13826)

3.4 电源

事件日志中包含屏幕电源状态,其中 0 表示屏幕关闭,1 表示屏幕打开,2 表示已锁屏。
日志范例如下:

grep screen_toggled bugreport-2015-10-18-16-52-22.txt
10-18 15:05:04.383   992   992 I screen_toggled: 1
10-18 15:05:07.010   992   992 I screen_toggled: 0
10-18 15:23:15.063   992   992 I screen_toggled: 1
10-18 15:23:25.684   992   992 I screen_toggled: 0
10-18 15:36:31.623   992   992 I screen_toggled: 1
10-18 15:36:37.660  3283  3283 I screen_toggled: 2

错误报告中还包含关于唤醒锁的统计信息,唤醒锁是应用开发者采用的一种机制,用于表明其应用需要设备保持开启状态。唤醒锁总时长统计信息仅跟踪唤醒锁实际负责使设备保持唤醒状态的时间,不包括屏幕处于开启状态的时间。此外,如果同时持有多个唤醒锁,系统会在它们之间分配唤醒锁时长。

4. 小结

本节课程我们主要学习了如何获取和分析错误报告。本节课程的重点如下:

  • 掌握如何获取错误报告;
  • 掌握如何分析常见日志。