nginx 请求后端服务，频繁卡 1 分钟

前端或 postman 调用 nginx 代理的后端接口，会频繁的卡一分钟（ 1m 0.16s ，正常请求 100ms 左右）。

服务端是在 100ms 左右就处理完成，并返回了响应日志，直接请求后端接口也是正常的 100ms

#user nobody; worker_processes 4;

events { use epoll; worker_connections 65535; }

http { include mime.types; default_type application/octet-stream;

#log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
#                  '$status $body_bytes_sent "$http_referer" '
#                  '"$http_user_agent" "$http_x_forwarded_for"';

#access_log  logs/access.log  main;

sendfile        on;
#tcp_nopush     on;

underscores_in_headers on;

keepalive_timeout  180;

#gzip  on;
include cnf/upstream_*.cnf;
server {
    listen       80;
    server_name  localhost;
    include cnf/pathrule.cnf;

    #charset koi8-r;

    #access_log  logs/host.access.log  main;

    location / {
        root   html;
        index  index.html index.htm;
    }

    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   html;
    }

}

}