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luxueshi 3 years ago
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+show-busy-java-threads
+# 从所有运行的Java进程中找出最消耗CPU的线程(缺省5个),打印出其线程栈
+ 
+# 缺省会自动从所有的Java进程中找出最消耗CPU的线程,这样用更方便
+# 当然你可以手动指定要分析的Java进程Id,以保证只会显示出那个你关心的那个Java进程的信息
+show-busy-java-threads -p <指定的Java进程Id>
+ 
+show-busy-java-threads -c <要显示的线程栈数>
+ 
+show-busy-java-threads <重复执行的间隔秒数> [<重复执行的次数>]
+# 多次执行;这2个参数的使用方式类似vmstat命令
+ 
+show-busy-java-threads -a <运行输出的记录到的文件>
+# 记录到文件以方便回溯查看
+ 
+show-duplicate-java-classes -S <存储jstack输出文件的目录>
+# 指定jstack输出文件的存储目录,方便记录以后续分析
+ 
+##############################
+# 注意:
+##############################
+# 如果Java进程的用户 与 执行脚本的当前用户 不同,则jstack不了这个Java进程
+# 为了能切换到Java进程的用户,需要加sudo来执行,即可以解决:
+sudo show-busy-java-threads
+ 
+show-busy-java-threads -s <指定jstack命令的全路径>
+# 对于sudo方式的运行,JAVA_HOME环境变量不能传递给root,
+# 而root用户往往没有配置JAVA_HOME且不方便配置,
+# 显式指定jstack命令的路径就反而显得更方便了
+ 
+# -m选项:执行jstack命令时加上-m选项,显示上Native的栈帧,一般应用排查不需要使用
+show-busy-java-threads -m
+# -F选项:执行jstack命令时加上 -F 选项(如果直接jstack无响应时,用于强制jstack),一般情况不需要使用
+show-busy-java-threads -F
+# -l选项:执行jstack命令时加上 -l 选项,显示上更多相关锁的信息,一般情况不需要使用
+# 注意:和 -m -F 选项一起使用时,可能会大大增加jstack操作的耗时
+show-busy-java-threads -l
+ 
+# 帮助信息
+$ show-busy-java-threads -h
+Usage: show-busy-java-threads [OPTION]... [delay [count]]
+Find out the highest cpu consumed threads of java, and print the stack of these threads.
+ 
+Example:
+  show-busy-java-threads       # show busy java threads info
+  show-busy-java-threads 1     # update every 1 second, (stop by eg: CTRL+C)
+  show-busy-java-threads 3 10  # update every 3 seconds, update 10 times
+ 
+Output control:
+  -p, --pid <java pid>      find out the highest cpu consumed threads from
+                            the specified java process, default from all java process.
+  -c, --count <num>         set the thread count to show, default is 5.
+  -a, --append-file <file>  specifies the file to append output as log.
+  -S, --store-dir <dir>     specifies the directory for storing intermediate files, and keep files.
+                            default store intermediate files at tmp dir, and auto remove after run.
+                            use this option to keep files so as to review jstack/top/ps output later.
+  delay                     the delay between updates in seconds.
+  count                     the number of updates.
+                            delay/count arguments imitates the style of vmstat command.
+ 
+jstack control:
+  -s, --jstack-path <path>  specifies the path of jstack command.
+  -F, --force               set jstack to force a thread dump.
+                            use when jstack <pid> does not respond (process is hung).
+  -m, --mix-native-frames   set jstack to print both java and native frames (mixed mode).
+  -l, --lock-info           set jstack with long listing. Prints additional information about locks.
+ 
+cpu usage calculation control:
+  -d, --top-delay           specifies the delay between top samples, default is 0.5 (second).
+                            get thread cpu percentage during this delay interval.
+                            more info see top -d option. eg: -d 1 (1 second).
+  -P, --use-ps              use ps command to find busy thread(cpu usage) instead of top command,
+                            default use top command, because cpu usage of ps command is expressed as
+                            the percentage of time spent running during the *entire lifetime*
+                            of a process, this is not ideal in general.
+ 
+Miscellaneous:
+  -h, --help                display this help and exit.