得到进程的pid：
ps -ef | grep process_name | grep -v "grep" | awk '{print $2}'
查看进程的所有线程
# ps mp 6648 -o THREAD,tid
USER %CPU PRI SCNT WCHAN USER SYSTEM TID
root 0.0 - - - - - -
root 0.0 24 - - - - 6648
root 0.0 21 - - - - 6650
root 1.0 24 - - - - 14214
root 0.0 23 - futex_ - - 14216
root 0.0 22 - 184466 - - 15374
root 0.0 23 - 184466 - - 15376
root 0.0 23 - 184466 - - 15378
root 0.0 23 - 184466 - - 15380
root 0.0 23 - 184466 - - 15392
root 0.0 23 - 184466 - - 15394
root 0.0 23 - 184466 - - 15398
查看所有子进程：
# pstree -p 6648
agent_executor(6648)─┬─tar(15601)───gzip(15607)
├─{agent_executor}(6650)
├─{agent_executor}(14214)
├─{agent_executor}(14216)
├─{agent_executor}(15374)
├─{agent_executor}(15376)
├─{agent_executor}(15378)
├─{agent_executor}(15380)
├─{agent_executor}(15392)
├─{agent_executor}(15394)
└─{agent_executor}(15398)