Nginx fastcgi_cache 不适用于一个 WP 站点（但对于 time.php 在不同的虚拟主机上工作正常）

我正在使用 fpm php 5.5 运行 Ubuntu nginx 1.8，在一个站点上我能够使缓存正常工作（通过简单的时间输出）<?php echo time();?>显示：

Connection:keep-alive
Content-Encoding:gzip
Content-Type:text/html
Date:Fri, 08 Jan 2016 14:04:00 GMT
Fastcgi-Cache:HIT
Server:nginx/1.8.0
Transfer-Encoding:chunked
X-Powered-By:PHP/5.5.9-1ubuntu4.14

但是对于 WordPress 网站，标题始终显示（即使在注销和隐身时）：

Cache-Control:no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Connection:keep-alive
Content-Encoding:gzip
Content-Type:text/html; charset=UTF-8
Date:Fri, 08 Jan 2016 14:02:42 GMT
Expires:Thu, 19 Nov 1981 08:52:00 GMT
Fastcgi-Cache:BYPASS
Link:<http://mywpsite.com/wp-json/>; rel="https://api.w.org/"
Link:<http://mywpsite.com/>; rel=shortlink
Pragma:no-cache
Server:nginx/1.8.0
Transfer-Encoding:chunked
Vary:Accept-Encoding
X-Powered-By:PHP/5.5.9-1ubuntu4.14

从 wiki 我尝试了不同的设置并压缩到以下单个文件（tester.com 有效，而 mywpsite.com 没有 - 这些是我在我的主机文件中设置的别名，并且肯定命中了正确的服务器）https://codex .wordpress.org/Nginx。

猫 /etc/nginx/nginx.conf

user www-data;
worker_processes 4;
pid /run/nginx.pid;

events {
        worker_connections 1024;
        # multi_accept on;
}

http {
        fastcgi_cache_key "$scheme$request_method$host$request_uri";

        sendfile on;
        tcp_nopush on;
        tcp_nodelay on;
        keepalive_timeout 65;
        types_hash_max_size 2048;

        include /etc/nginx/mime.types;
        default_type application/octet-stream;

        gzip on;
        gzip_disable "msie6";

        application/xml+rss text/javascript;

        # Upstream to abstract backend connection(s) for PHP.
        upstream php {
                #this should match value of "listen" directive in php-fpm pool
                server unix:/var/run/php5-fpm.sock;
        }

        include /etc/nginx/conf.d/*.conf;
        include /etc/nginx/sites-enabled/*;

        add_header Fastcgi-Cache $upstream_cache_status;
}

猫 /etc/nginx/sites-available/tester.com

fastcgi_cache_path /home/tester.com/cache levels=1:2 keys_zone=MYAPP:100m inactive=60m;

server {
    listen   80;
    server_name tester.com;

    root /home/tester.com/public_html;
    index index.php index.html index.htm;

    location / {
        try_files $uri $uri/ /index.html;
    }

    location ~ \.php$ {
        try_files $uri =404;
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        fastcgi_index index.php;
        include fastcgi_params;
        fastcgi_cache MYAPP;
        fastcgi_cache_valid 200 60m;
    }
}

猫 /etc/nginx/sites-available/mywpsite.com

fastcgi_cache_path /home/mywpsite.com/cache levels=1:2 keys_zone=MYWPSITE:100m inactive=60m;

server {
        server_name mywpsite.com;
        root /home/mywpsite.com/public_html;

        index index.php;

        location = /favicon.ico {
                log_not_found off;
                access_log off;
        }

        location = /robots.txt {
                allow all;
                log_not_found off;
                access_log off;
        }

        location ~ /\. {
                access_log off;
                log_not_found off;
                deny all;
        }

        location ~* /(?:uploads|files)/.*\.php$ {
                deny all;
        }

        location / {
                try_files $uri $uri/ /index.php?$args;
        }

        # Add trailing slash to */wp-admin requests.
        rewrite /wp-admin$ $scheme://$host$uri/ permanent;

        set $skip_cache 0;

        if ($request_method = POST) {
            set $skip_cache 1;
        }

        if ($query_string != "") {
            set $skip_cache 1;
        }

        if ($request_uri ~* "/wp-admin/|/xmlrpc.php|wp-.*.php|/feed/|index.php|sitemap(_index)?.xml") {
            set $skip_cache 1;
        }

        if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass|wordpress_no_cache|wordpress_logged_in") {
            set $skip_cache 1;
        }

        location ~* ^.+\.(ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|rss|atom|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf)$ {
               access_log off; log_not_found off; expires max;
        }

        fastcgi_cache_bypass $skip_cache;
        fastcgi_no_cache $skip_cache;
        fastcgi_cache MYWPSITE;
        fastcgi_cache_valid 60m;

        location ~ [^/]\.php(/|$) {
                fastcgi_split_path_info ^(.+?\.php)(/.*)$;
                if (!-f $document_root$fastcgi_script_name) {
                        return 404;
                }
                # This is a robust solution for path info security issue and works with "cgi.fix_pathinfo = 1" in /etc/php.ini (default)

                include fastcgi.conf;
                fastcgi_index index.php;
                #       fastcgi_intercept_errors on;
                fastcgi_pass php;

                fastcgi_cache_bypass $skip_cache;
                fastcgi_no_cache $skip_cache;

                fastcgi_cache MYWPSITE;
                fastcgi_cache_valid 200 60m;
        }

        location ~ /purge(/.*) {
                fastcgi_cache_purge MYWPSITE"$scheme$request_method$host$1";
        }
}

道歉，因为我确信这是一些愚蠢的事情，但经过几个深夜后，我会很感激一些新鲜的眼睛来看待这个问题。