架构--缓存知识

缓存体系是根据http体系来写的

 

nginx代理缓存配置

mkdir -p /data/cdn_cache

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[root@linux-node1 ~]#/etc/nginx/conf.d/proxy.conf

#CDN
proxy_temp_path /data/cdn_cache/proxy_temp_dir;
proxy_cache_path /data/cdn_cache/proxy_cache_dir levels=1:2 keys_zone=cache_one:50m inactive=1d max_size=1g;
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_next_upstream error timeout invalid_header http_500 http_502 http_503 http_404;
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[root@linux-node1 ~]# /etc/nginx/conf.d/upstream.conf

upstream www.example.com.pool
{
        server 192.168.56.12:8080 weight=10 max_fails=3;
}
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[root@linux-node1 ~]# vim /etc/nginx/conf.d/www.example.com.conf

server
{
    listen 80;
    server_name www.example.com;
    access_log logs/www.example.com-access.log main;
    location ~ .*.(gif|jpg|png|html|htm|css|js|ico|swf|pdf)$
    {
	#Proxy 
	proxy_redirect off;
        proxy_next_upstream http_502 http_504 http_404 error timeout invalid_header;
        proxy_set_header            Host $host;
        proxy_set_header            X-real-ip $remote_addr;
        proxy_set_header            X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_pass    http://www.example.com;

	#Use Proxy Cache
	proxy_cache cache_one;
	proxy_cache_key "$host$request_uri";
	add_header Cache "$upstream_cache_status";
	proxy_cache_valid  200 304 301 302 8h;
	proxy_cache_valid 404 1m;
	proxy_cache_valid  any 2d;
    }
    location /
    {
                proxy_redirect off;
                proxy_next_upstream http_502 http_504 http_404 error timeout invalid_header;
                proxy_set_header            Host $host;
                proxy_set_header            X-real-ip $remote_addr;
                proxy_set_header            X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_pass    http://www.example.com;
                client_max_body_size 40m;
                client_body_buffer_size 128k;
                proxy_connect_timeout 60;
                proxy_send_timeout 60;
                proxy_read_timeout 60;
                proxy_buffer_size 64k;
                proxy_buffers 4 32k;
                proxy_busy_buffers_size 64k;

    }
}


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[root@linux-node2 ~]  vim vhost.example.com.conf
server {
        listen 8080;
        server_name www.example.com;
        location / {
            root /data/www/www;
            index index.html index.htm;
        }
        error_log    logs/error_www.example.com.log error;
        access_log    logs/access_www.example.com.log    main;
}

windoes 绑定主机名访问 www.example.com，返回node1服务器发现有缓存了

 如果用户访问后就回有缓存，但是如果网页文件跟新了，但是用户还是访问的缓存这样就回出现问题，则需要删缓存流程：

#!/bin/bash

cache_purge(){
PURGE_URL=$1
    URL_NAME=$(echo -n $PURGE_URL | md5sum | awk '{print $1}')
    FILE_NAME=$(echo $URL_NAME  | awk '{print "/data/cdn_cache/proxy_cache_dir/"substr($0,length($0),1)"/"substr($0,length($0)-2,2)"/"$0}')
    rm -rf $FILE_NAME
}

purge_file(){
        PURGE_FILE=$1
        for url in $(cat $PURGE_FILE);do
                cache_purge $url
        done
}

purge_url(){
        PURGE_URL=$1
        cache_purge $PURGE_URL
}

usage(){
        echo $"Usage: $0 <url_file | 'url'>"
}

main (){
        if [ "$#" -ne 1 ];then
                usage;
        else
                if [ -f $1 ];then
                        purge_file $1;
                else
                        purge_url $1;
                fi
        fi
}

main $1

[root@node1 ~]# sh a.sh www.example.com/index.html

通过MD5的方式找到缓存池的缓存，并把缓存删了

####web缓存

操作码缓存 ----php配置可以开启opcache     http://www.php.net/manual/zh/book.opcache.php

                                                                     http://www.php.net/manual/zh/opcache.configuration.php

web服务器缓存--apache(mod_cache),nginx(fastCGI缓存，proxy cache)

####应用层

                    ｜----动态内容缓存      缓存动态输出

应用服务---  ｜----页面静态化          动态页面静态化，需要专门用于静态化的CMS

　　　　　  ｜----local   cache        应用本地缓存，php(yac,xcache) java (ehcache)

                   

                    ｜----分布式缓存         mamcache,radis等 

数据层-----   ｜----数据库mysql       mysql自身缓存，innodb缓存，MYISAM缓存

                                           

系统层-----   ｜---操作系统-----cpu cache    L1（数据缓存，指令缓存）L2 L3

                                         -----内存 cache  内存高速缓存，page cache 

物理层-----    ｜ ----raid卡-----raid cache  磁盘整列缓存（raid卡可以控制是否实用磁盘高速缓存）

                     ｜ ----磁盘  ---- disk cache 磁盘高速缓存