通过Nginx缓存加速提高WordPress网站访问速度

博客开通以来，主要记录学习和使用过程中遇到的问题及解决方案。文章风格偏向自娱自乐，因此访问量较少，一台1核2G的服务器足以支撑网站的正常运行。

后来本站引入三个页面，这三个页面应该对有上外网需求的网友很有帮助，也给本站带来了很大的流量。本站用的WordPress程序，尝试过安装各种缓存插件（super cache, w3 total cache等）加速运行，但是低配的vps依然难以支持这么大的访问量。通过日志可以看到随着访问量的增加，php-fpm进程增多，Mysql的连接和线程增多，接着出现OOM，然后系统kill掉占用内存最大的Mysql进程，于是网站进入503宕机模式。

买更好的vps能解决访问量大的问题，但是要花更多的钱。做为一个技术宅，首先想到的当然是如何榨干现有机器来支撑大流量。做过的尝试包括切换到比WordPress性能更好的Ghost，参考：尝试Ghost 。但是相对于WordPress，Ghost的生态远没有那么成熟，最终放弃了。

左思右想下，终极解决办法是用Nginx缓存，最初的文章可参考：Nginx配置fastcgi cache。fastcgi_cache的好处是大部分用户的请求不用后端php-fpm打交道，直接发送缓存的静态页面，速度上甩各种WordPress插件好几条街！相比之下wordpress的各种插件还要执行php，也避免不了访问数据库，弱爆了！

自从使用了nginx缓存，网站平稳运行，再也没有出现过宕机的现象。同时vps的cpu和内存占用率直线下降，再也无需担心vps的配置问题，感觉再来10倍流量博客也撑得住！

因为nginx稳如狗的体验，所以现在对于博客类读多写少的产品都是强推nginx缓存（fastcgi缓存或者proxy缓存）。鉴于可能帮到一些网友，现贴出 /etc/nginx/nginx.conf 配置文件供网友参考（包含ssl设置和gzip部分）：

# 文件： /etc/nginx/nginx.conf

# For more information on configuration, see:

#   * Official English Documentation: http://nginx.org/en/docs/

#   * Official Russian Documentation: http://nginx.org/ru/docs/

user nginx;

worker_processes auto;

error_log /var/log/nginx/error.log;

pid /run/nginx.pid;

# Load dynamic modules. See /usr/share/nginx/README.dynamic.

include /usr/share/nginx/modules/*.conf;

events {

    worker_connections 1024;

}

http {

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '

                      '$status $body_bytes_sent "$http_referer" '

                      '"$http_user_agent" "$http_x_forwarded_for" "$request_time"';

    access_log  /var/log/nginx/access.log  main buffer=32k flush=30s;

    server_tokens       off;

    client_max_body_size 100m;

    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;

    # ssl配置

    ssl_protocols TLSv1.2 TLSv1.3;

    ssl_ciphers ECDHE-RSA-AES256-GCM-SHA512:DHE-RSA-AES256-GCM-SHA512:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384;

    ssl_ecdh_curve secp384r1;

    ssl_prefer_server_ciphers on;

    ssl_session_cache shared:SSL:10m;

    ssl_session_timeout 10m;

    ssl_session_tickets off;

    ssl_stapling on; # Requires nginx >= 1.3.7

    ssl_stapling_verify on; # Requires nginx => 1.3.7

    add_header Strict-Transport-Security "max-age=63072000; preload";

    #add_header X-Frame-Options DENY;

    add_header X-Frame-Options SAMEORIGIN;

    add_header X-Content-Type-Options nosniff;

    add_header X-XSS-Protection "1; mode=block";

    # 请按照自己的需求更改

    fastcgi_cache_path /var/cache/nginx/tlanyan levels=1:2 keys_zone=tlanyan:10m inactive=30m use_temp_path=off; 

    fastcgi_cache_key $request_method$scheme$host$request_uri;

    # note: can also use HTTP headers to form the cache key, e.g.

    #fastcgi_cache_key $scheme$request_method$host$request_uri$http_x_custom_header;

    #fastcgi_cache_lock on;

    fastcgi_cache_use_stale error timeout invalid_header updating http_500;

    fastcgi_cache_valid 200 301 302 10h;

    fastcgi_cache_valid 404 10m;

    fastcgi_ignore_headers Expires Set-Cookie Vary;

    # gzip 配置

    gzip on;

    gzip_min_length  1k;

    gzip_buffers     4 16k;

    gzip_comp_level 7;

    gzip_types

        text/css

        text/plain

        text/javascript

        application/javascript

        application/json

        application/x-javascript

        application/xml

        application/xml+rss

        application/xhtml+xml

        application/x-font-ttf

        application/x-font-opentype

        application/vnd.ms-fontobject

        image/svg+xml

        image/x-icon

        application/rss+xml

        application/atom_xml

        image/jpeg

        image/gif

        image/png

        image/icon

        image/bmp

        image/jpg;

    gzip_vary on;

    # Load modular configuration files from the /etc/nginx/conf.d directory.

    # See http://nginx.org/en/docs/ngx_core_module.html#include

    # for more information.

    include /etc/nginx/conf.d/*.conf;

}

以及用于WordPress站点的网站配置文件（/etc/nginx/conf.d/tlanyan.conf）:

server {

    listen 80;

    listen [::]:80;

    server_name www.tlanyan.me tlanyan.me; # 请换成自己的域名

    rewrite ^(.*) https://$server_name$1 permanent;

}

server {

    listen       443 ssl http2;

    listen       [::]:443 ssl http2;

    server_name www.tlanyan.me tlanyan.me; # 请换成自己的域名

    charset utf-8;

    ssl_certificate /etc/nginx/conf.d/tlanyan.pem;  # 请换成自己的证书和密钥

    ssl_certificate_key /etc/nginx/conf.d/tlanyan.key;

    set $host_path "/var/www/tlanyan";  # 请改成自己的路径

    access_log  /var/log/nginx/tlanyan.access.log  main buffer=32k flush=30s;

    error_log /var/log/nginx/tlanyan.error.log;

    root   $host_path;

    # 缓存标记

    set $skip_cache 0;

    if ($query_string != "") {

        set $skip_cache 1;

    }

    if ($request_uri ~* "/wp-admin/|/xmlrpc.php|wp-.*.php|/feed/|sitemap(_index)?.xml") {

        set $skip_cache 1;

    }

    # 登录用户或发表评论者

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

        set $skip_cache 1;

    }

    location = / {

        index  index.php index.html;

        try_files /index.php?$args /index.php?$args;

    }

    location / {

        index  index.php index.html;

        try_files $uri $uri/ /index.php?$args;

    }

    location ~ ^/\.user\.ini {

            deny all;

    }

    location ~ \.php$ {

        try_files $uri =404;

        fastcgi_index index.php;

        fastcgi_pass   127.0.0.1:9000;

        fastcgi_cache tlanyan;

        fastcgi_cache_valid 200 301 302 30m;

        fastcgi_cache_valid 404 10m;

        fastcgi_cache_bypass $skip_cache;

        fastcgi_no_cache $skip_cache;

        fastcgi_cache_lock on;

        include fastcgi_params;

        fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;

    }

    location ~ \.(js|css|png|jpg|gif|swf|ico|pdf|mov|fla|zip|rar|jpeg)$ {

        expires max;

        access_log off;

        try_files $uri =404;

    }

}

上述配置对最新版的Nginx测试有效，详细配置指令请参考Nginx官方文档。