Workers CPU leak [epoll_wait,epoll_ctl]

[Maxim Dounin]

Hello!

On Sat, Jul 29, 2017 at 05:35:08AM -0400, lamsung wrote:

> Hello, I have strange issuses with nginx workers. For some time after start
> Nginx I notice that some process of workers cause high load to CPU (
> principally sys CPU). 

[...]

> Nginx has such version and modules: 
> 
> nginx version: nginx/1.9.11 
> built with OpenSSL 1.0.2f 28 Jan 2016 
> TLS SNI support enabled 
> configure arguments: --prefix=/usr --conf-path=/etc/nginx/nginx.conf
> --error-log-path=/var/log/nginx/error_log --pid-path=/run/nginx.pid
> --lock-path=/run/lock/nginx.lock --with-cc-opt=-I/usr/include
> --with-ld-opt=-L/usr/lib64 --http-log-path=/var/log/nginx/access_log
> --http-client-body-temp-path=/var/lib/nginx/tmp/client
> --http-proxy-temp-path=/var/lib/nginx/tmp/proxy
> --http-fastcgi-temp-path=/var/lib/nginx/tmp/fastcgi
> --http-scgi-temp-path=/var/lib/nginx/tmp/scgi
> --http-uwsgi-temp-path=/var/lib/nginx/tmp/uwsgi --with-file-aio --with-ipv6
> --with-pcre --with-threads --without-http_autoindex_module
> --without-http_fastcgi_module --without-http_geo_module
> --without-http_limit_req_module --without-http_limit_conn_module
> --without-http_memcached_module --without-http_uwsgi_module
> --with-http_flv_module --with-http_gzip_static_module --with-http_mp4_module
> --with-http_perl_module
> --add-module=external_module/headers-more-nginx-module-0.261
> --add-module=external_module/ngx_estreaming_module-0.01
> --add-module=external_module/ngx_slice_module-0.01 --with-http_ssl_module
> --without-mail_imap_module --without-mail_pop3_module
> --without-mail_smtp_module --user='www --group=www' 
> 
> and using for video streaming. 
> 
> Has anyone encountered such behavior ? Help please.

An obvious first step would be to try to reproduce the problem 
without 3rd party modules.

Trying something newer than 1.9.11 is also recommended - it is not 
supported since release of nginx 1.9.12 on 24 Feb 2016.  Current 
versions are 1.13.3 (mainline) and 1.12.1 (stable).

-- 
Maxim Dounin
http://nginx.org/