1：定位进程 top命令查看所有进程占系统CPU的排序，它是Linux下常用的性能分析工具，能够实时显示系统中各个进程的资源占用状况，类似于Windows的任务管理器。
2：定位线程 top -Hp PID(进程号)
3:定位代码 根据该16进制值去打印的堆栈日志内查询，查看该线程所驻留的方法位置。通过jstack命令
jstack 17850|grep 45d8 -A 30
"pool-1-thread-11" #20 prio=5 os_prio=0 tid=0x00007fc860352800 nid=0x45d8 runnable [0x00007fc8417d2000]
java.lang.Thread.State: RUNNABLE
at java.io.FileOutputStream.writeBytes(Native Method)
at java.io.FileOutputStream.write(FileOutputStream.java:326)
at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:82)
at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:140)
- locked <0x00000006c6c2e708> (a java.io.BufferedOutputStream)
at java.io.PrintStream.write(PrintStream.java:482)
- locked <0x00000006c6c10178> (a java.io.PrintStream)
at sun.nio.cs.StreamEncoder.writeBytes(StreamEncoder.java:221)
at sun.nio.cs.StreamEncoder.implFlushBuffer(StreamEncoder.java:291)
at sun.nio.cs.StreamEncoder.flushBuffer(StreamEncoder.java:104)
- locked <0x00000006c6c26620> (a java.io.OutputStreamWriter)
at java.io.OutputStreamWriter.flushBuffer(OutputStreamWriter.java:185)
at java.io.PrintStream.write(PrintStream.java:527)
- eliminated <0x00000006c6c10178> (a java.io.PrintStream)
at java.io.PrintStream.print(PrintStream.java:597)
at java.io.PrintStream.println(PrintStream.java:736)
- locked <0x00000006c6c10178> (a java.io.PrintStream)
at com.demo.guava.HardTask.call(HardTask.java:18)
at com.demo.guava.HardTask.call(HardTask.java:9)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"pool-1-thread-10" #19 prio=5 os_prio=0 tid=0x00007fc860345000 nid=0x45d7 waiting on condition [0x00007fc8418d3000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c6c14178> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
jstack PID(进程号)|grep aef(进程号下的线程号，且转为16进制) -A 200
