pstack说明
- 在程序运行过程中，如果发生阻塞或者work状态，可以使用该命令显示进程的栈跟踪。
- 该命令必须由进程的属主或root运行。
- 使用该命令来确定进程挂起的位置。
- 该命令允许使用的唯一选项是要检查的进程的 PID，即运行格式为：
pstack pid。
pstack应用
安装pstree工具
pstree以树结构显示进程，centos7上默认没有安装psmisc包。
# 在 Mac OS 上安装
brew install pstree
# 在 Fedora/Red Hat/CentOS 安装
yum -y install psmisc
# 在 Ubuntu/Debian 上安装
apt-get install psmisc
pstree使用
- 查看某个服务的线程信息
pstree -p work | grep redis
work为工作用户，-p为显示进程识别码，如下图所示：redis共启动了3个子线程，加上主线程共4个线程。
pstree -p redis | grep redis
redis-server(1190)-+-{redis-server}(1191)
|-{redis-server}(1192)
`-{redis-server}(1193)
- 查看某个进程的所有线程
[root@jolay ~]# ps -Lf 1190
UID PID PPID LWP C NLWP STIME TTY STAT TIME CMD
redis 1190 1 1190 1 4 May20 ? Ssl 174:44 /home/q/redis/redis10010/bin/redis-server *:10010
redis 1190 1 1191 0 4 May20 ? Ssl 0:00 /home/q/redis/redis10010/bin/redis-server *:10010
redis 1190 1 1192 0 4 May20 ? Ssl 0:00 /home/q/redis/redis10010/bin/redis-server *:10010
redis 1190 1 1193 0 4 May20 ? Ssl 0:00 /home/q/redis/redis10010/bin/redis-server *:10010
pstack使用
- 查看某个进程的pstack信息
[root@jolay ~]# pstack 1190
Thread 4 (Thread 0x7f836dfff700 (LWP 1191)):
#0 0x00007f836ed85965 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x0000000000485b26 in bioProcessBackgroundJobs (arg=0x0) at bio.c:176
#2 0x00007f836ed81dd5 in start_thread () from /lib64/libpthread.so.0
#3 0x00007f836eaaaead in clone () from /lib64/libc.so.6
Thread 3 (Thread 0x7f836d7fe700 (LWP 1192)):
#0 0x00007f836ed85965 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x0000000000485b26 in bioProcessBackgroundJobs (arg=0x1) at bio.c:176
#2 0x00007f836ed81dd5 in start_thread () from /lib64/libpthread.so.0
#3 0x00007f836eaaaead in clone () from /lib64/libc.so.6
Thread 2 (Thread 0x7f836cffd700 (LWP 1193)):
#0 0x00007f836ed85965 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x0000000000485b26 in bioProcessBackgroundJobs (arg=0x2) at bio.c:176
#2 0x00007f836ed81dd5 in start_thread () from /lib64/libpthread.so.0
#3 0x00007f836eaaaead in clone () from /lib64/libc.so.6
Thread 1 (Thread 0x7f836f8b6f80 (LWP 1190)):
#0 0x00007f836eaab483 in epoll_wait () from /lib64/libc.so.6
#1 0x000000000042908e in aeApiPoll (tvp=<optimized out>, eventLoop=0x7f836e44c0a0) at ae_epoll.c:112
#2 aeProcessEvents (eventLoop=0x7f836e44c0a0, flags=11) at ae.c:411
#3 0x000000000042952b in aeMain (eventLoop=0x7f836e44c0a0) at ae.c:501
#4 0x000000000043184f in main (argc=<optimized out>, argv=<optimized out>) at server.c:4603
- 格式化查看pstack信息
- 生成脚本
(
cat <<EOF
#!/usr/bin/python3
import sys
import subprocess
import re
if len(sys.argv) != 2:
print('Please input a PID.')
exit(1)
status, out = subprocess.getstatusoutput('pstack {pid}'.format(pid=sys.argv[1]))
if status != 0:
print('Please install pstack.')
exit(1)
lst = re.split('Thread \d+.*:(.*)', out)
result = {}
for item in lst:
item = item.strip()
if item != '':
if item in result:
result[item] += 1
else:
result[item] = 1
result = sorted(result.items(), key=lambda e:e[1], reverse=True)
for item in result:
print('Count: ', item[1])
print(item[0])
print('-----------------------------------------------')
EOF
) > ./pstack.py
chmod +x pstack.py
- 执行脚本
[root@jolay ~]# ./pstack.py 1190
Count: 1
#0 0x00007f836ed85965 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x0000000000485b26 in bioProcessBackgroundJobs (arg=0x1) at bio.c:176
#2 0x00007f836ed81dd5 in start_thread () from /lib64/libpthread.so.0
#3 0x00007f836eaaaead in clone () from /lib64/libc.so.6
-----------------------------------------------
Count: 1
#0 0x00007f836eaab483 in epoll_wait () from /lib64/libc.so.6
#1 0x000000000042908e in aeApiPoll (tvp=<optimized out>, eventLoop=0x7f836e44c0a0) at ae_epoll.c:112
#2 aeProcessEvents (eventLoop=0x7f836e44c0a0, flags=11) at ae.c:411
#3 0x000000000042952b in aeMain (eventLoop=0x7f836e44c0a0) at ae.c:501
#4 0x000000000043184f in main (argc=<optimized out>, argv=<optimized out>) at server.c:4603
-----------------------------------------------
Count: 1
#0 0x00007f836ed85965 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x0000000000485b26 in bioProcessBackgroundJobs (arg=0x2) at bio.c:176
#2 0x00007f836ed81dd5 in start_thread () from /lib64/libpthread.so.0
#3 0x00007f836eaaaead in clone () from /lib64/libc.so.6
-----------------------------------------------
Count: 1
#0 0x00007f836ed85965 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x0000000000485b26 in bioProcessBackgroundJobs (arg=0x0) at bio.c:176
#2 0x00007f836ed81dd5 in start_thread () from /lib64/libpthread.so.0
#3 0x00007f836eaaaead in clone () from /lib64/libc.so.6
-----------------------------------------------
