linux系统中pstack命令怎么用

pstack用来跟踪进程栈，这个命令在排查进程问题时非常有用，比如我们发现一个服务一直处于work状态（如假死状态，好似死循环），使用这个命令就能轻松定位问题所在。

实例

pstree以树结构显示进程

pstree -p work | grep adsshd(22669)---bash(22670)---ad_preprocess(4551)-+-{ad_preprocess}(4552)                                               |-{ad_preprocess}(4553)                                               |-{ad_preprocess}(4554)                                               |-{ad_preprocess}(4555)                                               |-{ad_preprocess}(4556)                                               `-{ad_preprocess}(4557)

work为工作用户，-p为显示进程识别码，ad_preprocess共启动了6个子线程，加上主线程共7个线程。

ps -Lf 4551UID        PID  PPID   LWP  C NLWP STIME TTY      stat   time CMDwork      4551 22670  4551  2    7 16:30 pts/2    Sl+    0:02 ./ad_preprocesswork      4551 22670  4552  0    7 16:30 pts/2    Sl+    0:00 ./ad_preprocesswork      4551 22670  4553  0    7 16:30 pts/2    Sl+    0:00 ./ad_preprocesswork      4551 22670  4554  0    7 16:30 pts/2    Sl+    0:00 ./ad_preprocesswork      4551 22670  4555  0    7 16:30 pts/2    Sl+    0:00 ./ad_preprocesswork      4551 22670  4556  0    7 16:30 pts/2    Sl+    0:00 ./ad_preprocesswork      4551 22670  4557  0    7 16:30 pts/2    Sl+    0:00 ./ad_preprocess

进程共启动了7个线程

pstack显示每个进程的栈跟踪：

pstack 4551Thread 7 (Thread 1084229984 (LWP 4552)):#0  0x000000302afc63dc in epoll_wait () from /lib64/tls/libc.so.6#1  0x00000000006f0730 in ub::EPollEx::poll ()#2  0x00000000006f172a in ub::NetReactor::callback ()#3  0x00000000006fbbbb in ub::UBTask::CALLBACK ()#4  0x000000302b80610a in start_thread () from /lib64/tls/libpthread.so.0#5  0x000000302afc6003 in clone () from /lib64/tls/libc.so.6#6  0x0000000000000000 in ?? ()Thread 6 (Thread 1094719840 (LWP 4553)):#0  0x000000302afc63dc in epoll_wait () from /lib64/tls/libc.so.6#1  0x00000000006f0730 in ub::EPollEx::poll ()#2  0x00000000006f172a in ub::NetReactor::callback ()#3  0x00000000006fbbbb in ub::UBTask::CALLBACK ()#4  0x000000302b80610a in start_thread () from /lib64/tls/libpthread.so.0#5  0x000000302afc6003 in clone () from /lib64/tls/libc.so.6#6  0x0000000000000000 in ?? ()Thread 5 (Thread 1105209696 (LWP 4554)):#0  0x000000302b80baa5 in __nanosleep_nocancel ()#1  0x000000000079e758 in comcm::ms_sleep ()#2  0x00000000006c8581 in ub::UbClientManager::healthyCheck ()#3  0x00000000006c8471 in ub::UbClientManager::start_healthy_check ()#4  0x000000302b80610a in start_thread () from /lib64/tls/libpthread.so.0#5  0x000000302afc6003 in clone () from /lib64/tls/libc.so.6#6  0x0000000000000000 in ?? ()Thread 4 (Thread 1115699552 (LWP 4555)):#0  0x000000302b80baa5 in __nanosleep_nocancel ()#1  0x0000000000482b0e in armor::armor_check_thread ()#2  0x000000302b80610a in start_thread () from /lib64/tls/libpthread.so.0#3  0x000000302afc6003 in clone () from /lib64/tls/libc.so.6#4  0x0000000000000000 in ?? ()Thread 3 (Thread 1126189408 (LWP 4556)):#0  0x000000302af8f1a5 in __nanosleep_nocancel () from /lib64/tls/libc.so.6#1  0x000000302af8f010 in sleep () from /lib64/tls/libc.so.6#2  0x000000000044c972 in Business_config_manager::run ()#3  0x0000000000457b83 in Thread::run_thread ()#4  0x000000302b80610a in start_thread () from /lib64/tls/libpthread.so.0#5  0x000000302afc6003 in clone () from /lib64/tls/libc.so.6#6  0x0000000000000000 in ?? ()Thread 2 (Thread 1136679264 (LWP 4557)):#0  0x000000302af8f1a5 in __nanosleep_nocancel () from /lib64/tls/libc.so.6#1  0x000000302af8f010 in sleep () from /lib64/tls/libc.so.6#2  0x00000000004524bb in Process_thread::sleep_period ()#3  0x0000000000452641 in Process_thread::run ()#4  0x0000000000457b83 in Thread::run_thread ()#5  0x000000302b80610a in start_thread () from /lib64/tls/libpthread.so.0#6  0x000000302afc6003 in clone () from /lib64/tls/libc.so.6#7  0x0000000000000000 in ?? ()Thread 1 (Thread 182894129792 (LWP 4551)):#0  0x000000302af8f1a5 in __nanosleep_nocancel () from /lib64/tls/libc.so.6#1  0x000000302af8f010 in sleep () from /lib64/tls/libc.so.6#2  0x0000000000420d79 in Ad_preprocess::run ()#3  0x0000000000450ad0 in main ()