背景：发现app server在测试机经常CPU飙升到接近100%strace发现大量的stat系统调用：[root@app02 ~]# strace -p 2205 -C…stat("/home/ouyang/storyapi/xb_handlers/support/system/get_pop_ups_handler.py", {st_mode=S_IFREG|0644, st_size=4094, …}) = 0stat("/home/ouyang/storyapi/xb_dao/support/share/base/user_share_newpull_dao.py", {st_mode=S_IFREG|0644, st_size=3695, …}) = 0stat("/usr/lib/python2.7/site-packages/urllib3/exceptions.py", {st_mode=S_IFREG|0644, st_size=6603, …}) = 0stat("/home/ouyang/storyapi/xb_dao/pay/comic/record/init.py", {st_mode=S_IFREG|0644, st_size=0, …}) = 0stat("/usr/lib/python2.7/site-packages/urllib3/packages/init.py", ^Cstrace: Process 6134 detached <detached …>% time seconds usecs/call calls errors syscall —- ———– ———– ——— ——— —————-▽96.53 20.122361 17332 1161 252 futex 2.95 0.614242 2 328764 477 stat 0.35 0.073086 163 448 read 0.06 0.013246 166 80 select 0.04 0.008513 5 1721 1388 open 0.02 0.004120 2 1780 getdents 0.01 0.002841 5 531 fstat 0.01 0.002252 3 890 openat 0.01 0.001959 2 1226 close 0.01 0.001300 1 883 lstat 0.01 0.001283 7 174 munmap 0.00 0.000485 3 191 mmap 0.00 0.000161 3 51 lseek 0.00 0.000080 2 34 brk 0.00 0.000039 39 1 clone 0.00 0.000014 3 5 mprotect 0.00 0.000005 1 5 5 ioctl 0.00 0.000000 0 6 6 access 0.00 0.000000 0 12 fcntl—— ———– ———– ——— ——— —————-100.00 20.845987 337963 2128 total[root@app02 ~]# 分析：1、业务代码并没有很多针对文件相关的操作。2、看stat系统调用各个代码文件都有涉及到，怀疑是django的reload模块导致。尝试：启动服务器时增加–noreload选项[root@app02 ~]# cat /etc/supervisord.d/app.ini [program:app]user=rootenvironment= PATH="/usr/bin"directory=/home/ouyang/storyapicommand=python manage.py runserver 0.0.0.0:8002 –nothreading –noreloadredirect_stderr=truestdout_logfile=/home/ouyang/storyapi/log/super.logstderr_logfile=/home/ouyang/storyapi/log/super.errstartsecs=1stopwaitsecs=1stopasgroup=true结果：1、问题解决，没有大量的stat系统调用了；2、CPU稳定在1%。