ANR问题分析

问题1：今日头条ANR
复习步骤：
主要操作是频繁的从侧边栏拉出今日头条进行分屏操作，多次操作之后，应用发生了ANR，这个会导致手机短暂的在分屏栏中的应用界面黑屏并卡死。不过4-5秒之后又正常。
应用发生ANR的原因是自身主线程被阻塞导致。

"main" prio=5 tid=1 Blocked
      | group="main" sCount=1 dsCount=0 obj=0x74f9bbe8 self=0xe7084400
      | sysTid=28210 nice=0 cgrp=default sched=0/0 handle=0xe9dcd534
      | state=S schedstat=( 1345442830 9928953 492 ) utm=121 stm=13 core=3 HZ=100
      | stack=0xff3b6000-0xff3b8000 stackSize=8MB
      | held mutexes=
      at com.ss.android.common.applog.LogReaper.insertCrashLog(SourceFile:98)
      - waiting to lock <0x0d3fbd00> (a com.ss.android.common.applog.LogReaper) held by thread 34
      at com.ss.android.common.applog.AppLog.uncaughtException(SourceFile:1408)
      at u.aly.n.uncaughtException(SourceFile:34)
      at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1068)
      at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1063)

关键信息

waiting to lock <0x0d3fbd00> (a com.ss.android.common.applog.LogReaper) held by thread 34

因此，在下面的ANR日志总，查找tid==34

"LogReaper" prio=5 tid=34 TimedWaiting
      | group="main" sCount=1 dsCount=0 obj=0x12fcaba0 self=0xcb226e00
      | sysTid=28274 nice=0 cgrp=default sched=0/0 handle=0xc9f9b920
      | state=S schedstat=( 77341565 2692708 80 ) utm=7 stm=0 core=5 HZ=100
      | stack=0xc9e99000-0xc9e9b000 stackSize=1038KB
     | held mutexes=
      at java.lang.Object.wait!(Native method)
      - waiting on <0x00fc7065> (a java.util.concurrent.atomic.AtomicInteger)
      at java.lang.Object.wait(Object.java:407)
      at com.ss.android.action.b.d.a(SourceFile:216)
      at com.ss.android.newmedia.b.onLogSessionBatchEvent(SourceFile:468)
      at com.ss.android.common.applog.DBHelper.batchSession(SourceFile:616)
      - locked <0x0d4ff1c4> (a com.ss.android.common.applog.DBHelper)
      at com.ss.android.common.applog.LogReaper.switchSession(SourceFile:175)
      at com.ss.android.common.applog.LogReaper.switchSession(SourceFile:153)
      at com.ss.android.common.applog.LogReaper.processItem(SourceFile:122)
      - locked <0x0d3fbd00> (a com.ss.android.common.applog.LogReaper)
      at com.ss.android.common.applog.LogReaper.run(SourceFile:632)

关键信息：

waiting on <0x00fc7065> (a java.util.concurrent.atomic.AtomicInteger)

应用内代码阻塞引起的