nginx 报 accept4() failed (24: Too many open files)

nginx 报 accept4() failed (24: Too many open files)
ulimit -a
ulimit -n 204800
vim /etc/security/limits.conf
<domain> <type> <item> <value>
* soft nofile 204800
* hard nofile 204800
* soft nproc 1000000
* hard nproc 1000000

vi  nginx.conf

worker_processes auto;
worker_rlimit_nofile 65535;

nginx -t
nginx -s reload

cat /proc/nginx_worker_pid/limits