nginx缓存设置

一、静态缓存
目的：缓存nginx服务器的静态文件。如css,js,htm,html,jpg,gif,png,flv,swf，这些文件都不是经常更新。便于缓存以减轻服务器的压力。
实现：nginx proxy_cache可以将用户的请缓存到本地一个目录，当下一个请求时可以直接调取缓存文件，就不用去后端服务器去取文件了。
配置：打开配置文件/usr/local/nginx/conf/nginx.conf

user  www www;
worker_processes 2;
error_log  /var/log/nginx_error.log  crit;
worker_rlimit_nofile 65535;
events
{
  use epoll;
  worker_connections 65535;
}

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

  server_names_hash_bucket_size 128;
  client_header_buffer_size 32k;
  large_client_header_buffers 4 32k;
  client_max_body_size 8m;

  sendfile on;
  tcp_nopush     on;
  keepalive_timeout 0;
  tcp_nodelay on;

  fastcgi_connect_timeout 300;
  fastcgi_send_timeout 300;
  fastcgi_read_timeout 300;
  fastcgi_buffer_size 64k;
  fastcgi_buffers 4 64k;
  fastcgi_busy_buffers_size 128k;
  fastcgi_temp_file_write_size 128k;
  ##cache##
  proxy_connect_timeout 5;
  proxy_read_timeout 60;
  proxy_send_timeout 5;
  proxy_buffer_size 16k;
  proxy_buffers 4 64k;
  proxy_busy_buffers_size 128k;
  proxy_temp_file_write_size 128k;
  proxy_temp_path /home/temp_dir;
  proxy_cache_path /home/cache levels=1:2 keys_zone=cache_one:200m inactive=1d max_size=30g;
  ##end##

  gzip    on;
  gzip_min_length   1k;
  gzip_buffers   4 8k;
  gzip_http_version  1.1;
  gzip_types   text/plain application/x-javascript text/css  application/xml;
  gzip_disable "MSIE [1-6]\.";

  log_format  access  '$remote_addr - $remote_user [$time_local] "$request" '
             '$status $body_bytes_sent "$http_referer" '
             '"$http_user_agent" $http_x_forwarded_for';
  upstream appserver {
        server 192.168.1.251;
  }
  server {
        listen       80 default;
        server_name www.gangpao.com;
        location ~ .*\.(gif|jpg|png|htm|html|css|js|flv|ico|swf)(.*) {
              proxy_pass http://appserver;
              proxy_redirect off;
              proxy_set_header Host $host;
              proxy_cache cache_one;
              proxy_cache_valid 200 302 1h;
              proxy_cache_valid 301 1d;
              proxy_cache_valid any 1m;
              expires 30d;
        }
        location ~ .*\.(php)(.*){
             proxy_pass http://appserver;
             proxy_set_header        Host $host;
             proxy_set_header        X-Real-IP $remote_addr;
             proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
        }
        access_log /usr/local/nginx/logs/www.gangpao.com.log;
  }
}

红色部分是配置缓存的参数。
说明：
1、http段设置。
proxy_temp_path /home/temp_dir;设置临时目录
proxy_cache_path /home/cache levels=1:2 keys_zone=cache_one:200m inactive=1d max_size=30g;设置缓存目录为二级目录，共享内存区大小，非活动时间，最大容量，注意临时目录要跟缓存目录在同一个分区。
2、server段设置
请求静态文件设置。
proxy_cache cache_one;设置缓存共享内存区块，也就是keys_zone名称。
proxy_cache_valid 200 302 1h;设置http状态码为200,302缓存时间为1小时。
expires 30d;设置失期时间，为30天
请求动态文件设置。
proxy_pass http://appserver;不进行缓存，直接转到后端服务器。
测试：当客户端发起http请求时在服务器上会产一个缓存文件如

/home/cache/0/b9/8bd841b1c44ee5b91457eb561e44eb90 

二、动态缓存
fastcgi_cache作用是缓存fastcgi生成的内容，很多情况是php生成的动态内容
fastcgi_cache缓存减少了nginx与php的通信次数，更减轻了php和数据库的压力。
#定义缓存存放的文件夹
fastcgi_cache_path /tt/cache levels=1:2 keys_zone=NAME:2880m inactive=2d max_size=10G;
#定义缓存不同的url请求
fastcgi_cache_key "$scheme$request_method$host$uri$arg_filename$arg_x$arg_y";
server {
listen 8080;
server_name www.example .com;
location / {
root /www;
index index.html index.htm index.php;
}
location ~ (|.php)$ {
root /www;
fastcgi_pass 127.0.0.1:9000;
fastcgi_cache NAME;
fastcgi_cache_valid 200 48h;
fastcgi_cache_min_uses 1;
fastcgi_cache_use_stale error timeout invalid_header http_500;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;
include fastcgi.conf;
#设置缓存的过程中发现无法获取cookie，经查需要定义这句话
fastcgi_pass_header Set-Cookie;
}
log_format access '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" $http_x_forwarded_for';
access_log /httplogs/access.log access;
}