squid中cache_peer的sibling用法

我的配置：

http_port 9413 transparent
icp_port 3130
cache_peer 192.168.1.244 sibling 9413 3130
cache_peer 192.168.1.241 sibling 9413 3130

cache_mem 256 MB
cache_dir ufs /data/squid_cache 4096 16 256
cache_effective_user squid
cache_effective_group squid
dns_nameservers 202.103.224.68
cache_access_log /var/log/squid/access.log
cache_log /var/log/squid/cache.log
cache_store_log /var/log/squid/store.log
visible_hostname beihai365_bb
cache_mgr [e-mail]

logfile_rotate 10

acl all src 0.0.0.0/0.0.0.0
http_access allow all
#acl okicp src 0.0.0.0/0.0.0.0
#icp_access allow okicp

提高squid命中率和使用效率是每个系统管理员都希望的一件事，毕竟在现有资源中榨干每一份的资源是必须滴，使用nginx的按url做定向投递，自然能提高squid的命中和效率，但毕竟公司目前没有这个条件，这个自然没法子实施，我就想到了另外的一个方法，就是今天的主角，cache_peer中的 sibling。

先说说我的思路

如果有5台squid，每台的缓存空间是10G，估计每台能缓存静态文件110W个，如果前端放置f5或其他负载均衡设备，把所有请求的url 都采用轮询的方式投递给squid，那最终每台squid上缓存住的静态文件几乎都是相同的，对于一个中小型的网站来说110W量的静态文件已经几乎是所有的静态文件了，但对于以在线漫画，或者图片为服务的网站来讲，静态文件将远远不止这个数量。

如果能让每台squid上缓存的都是独立的静态文件，那这组服务器所能缓存的文件将是原来能力的5倍，当然，前面提到了nginx的按url做定向投递可以解决这个问题，但这不是我要说的重点，其实用squid自己的堆叠就可以实现了，即cache_peer里的sibling

sibling是通过icq向同伴squid发送请求，一旦在同伴squid中发现了缓存命中，则由这个缓存命中返回给客户端，如果没有发现则到parent的squid去拿或者到realserver去拿

有了这个概念那就是说如果http://www.aaa.ccc/a.jpg发送过来了，如果a上没有，就会到b上找，如果有就反给客户端，如果没有会再去c上找如果最后都没有由a到后端parent或者realserver上取

下面看一个例子，我用vmware模拟了两个linux，上面分别跑了一个squid，

a上的配置，a的ip：192.168.220.128

icp_port 3130

icp_access allow all

cache_peer 61.152.242.1 parent 80 0 no - query originserver name=www2
cache_peer_domain www2 www.tgbus.com

b上的配置，b的ip：192.168.220.130

icp_port 3130

icp_access allow all

cache_peer 192.168.220.128 sibling 80 3130 proxy - only name=cache
cache_peer 61.152.242.1 parent 80 0 no - query originserver name=www2
cache_peer_domain cache www.tgbus.com
cache_peer_domain www2 www.tgbus.com

测试

修改本机本机hosts，先把www.tgbus.com指向到192.168.220.128上访问一遍，让220.128上有一份静态的缓存

然后把www.tgbus.com指向到192.168.220.130上，然后访问，可以看下两台机器上的日志

a的

1233463229. 874 0 192. 168. 220. 130 UDP_MISS/000 42 ICP_QUERY http: / / www. tgbus. com/ - NONE / - -
1233463231. 555 0 192. 168. 220. 130 UDP_HIT/000 51 ICP_QUERY http: / / www. tgbus. com/style. css - NONE / - -
1233463231. 557 0 192. 168. 220. 130 TCP_IMS_HIT/304 210 GET http: / / www. tgbus. com/style. css - NONE / - text / css
1233463231. 596 0 192. 168. 220. 130 UDP_MISS/000 67 ICP_QUERY http: / / www. tgbus. com/index/domain/Images/3. jpg - NONE / - -
1233463231. 602 0 192. 168. 220. 130 UDP_HIT/000 59 ICP_QUERY http: / / www. tgbus. com/images/v3/lqs. jpg - NONE / - -
1233463231. 603 0 192. 168. 220. 130 UDP_MISS/000 67 ICP_QUERY http: / / www. tgbus. com/index/domain/Images/4. jpg - NONE / - -
1233463231. 605 0 192. 168. 220. 130 TCP_IMS_HIT/304 212 GET http: / / www. tgbus. com/images/v3/lqs. jpg - NONE / - image/jpeg
1233463231. 609 0 192. 168. 220. 130 UDP_HIT/000 67 ICP_QUERY http: / / www. tgbus. com/index/tvgame/images/1. jpg - NONE / - -
1233463231. 612 0 192. 168. 220. 130 TCP_IMS_HIT/304 212 GET http: / / www. tgbus. com/index/tvgame/images/1. jpg - NONE / - image/jpeg
1233463231. 615 0 192. 168. 220. 130 UDP_HIT/000 67 ICP_QUERY http: / / www. tgbus. com/index/tvgame/images/2. jpg - NONE / - -
1233463231. 618 0 192. 168. 220. 130 TCP_IMS_HIT/304 212 GET http: / / www. tgbus. com/index/tvgame/images/2. jpg - NONE / - image/jpeg
1233463231. 619 0 192. 168. 220. 130 UDP_HIT/000 67 ICP_QUERY http: / / www. tgbus. com/index/tvgame/images/4. jpg - NONE / - -
1233463231. 619 0 192. 168. 220. 130 UDP_HIT/000 58 ICP_QUERY http: / / www. tgbus. com/images/v3/mc. jpg - NONE / - -
1233463231. 623 1 192. 168. 220. 130 TCP_IMS_HIT/304 212 GET http: / / www. tgbus. com/index/tvgame/images/4. jpg - NONE / - image/jpeg
1233463231. 623 1 192. 168. 220. 130 TCP_IMS_HIT/304 212 GET http: / / www. tgbus. com/images/v3/mc. jpg - NONE / - image/jpeg

b的

1233490583. 540 269 192. 168. 220. 1 TCP_MISS/200 57811 GET http: / / www. tgbus. com/ - FIRST_UP_PARENT/www2 text / html
1233490585. 753 3 192. 168. 220. 1 TCP_MISS/304 271 GET http: / / www. tgbus. com/style. css - SIBLING_HIT/cache text / css
1233490585. 845 5 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/images/v3/lqs. jpg - SIBLING_HIT/cache image/jpeg
1233490585. 857 5 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/tvgame/images/1. jpg - SIBLING_HIT/cache image/jpeg
1233490585. 862 4 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/tvgame/images/2. jpg - SIBLING_HIT/cache image/jpeg
1233490585. 868 5 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/tvgame/images/4. jpg - SIBLING_HIT/cache image/jpeg
1233490585. 868 5 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/images/v3/mc. jpg - SIBLING_HIT/cache image/jpeg
1233490585. 871 4 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/tvgame/images/3. jpg - SIBLING_HIT/cache image/jpeg
1233490585. 873 3 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/tvgame/images/5. jpg - SIBLING_HIT/cache image/jpeg
1233490585. 885 4 192. 168. 220. 1 TCP_MISS/304 272 GET http: / / www. tgbus. com/Images/v3/hot. gif - SIBLING_HIT/cache image/gif
1233490585. 907 3 192. 168. 220. 1 TCP_MISS/304 272 GET http: / / www. tgbus. com/Images/v3/tvgame. gif - SIBLING_HIT/cache image/gif
1233490585. 943 3 192. 168. 220. 1 TCP_MISS/304 272 GET http: / / www. tgbus. com/Images/v3/league. gif - SIBLING_HIT/cache image/gif
1233490586. 382 555 192. 168. 220. 1 TCP_MISS/304 292 GET http: / / www. tgbus. com/index/domain/Images/3. jpg - FIRST_UP_PARENT/www2 -
1233490586. 477 11 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/comic/images/manhua01. jpg - SIBLING_HIT/cache image/jpeg
1233490586. 479 11 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/comic/images/manhua02. jpg - SIBLING_HIT/cache image/jpeg
1233490586. 479 11 192. 168. 220. 1 TCP_MISS/304 273 GET http: / / www. tgbus. com/index/comic/images/manhua03. jpg - SIBLING_HIT/cache image/jpeg

由上面可以看到，在b上tcp_miss的大部分在a上都是sibling_hit的，这样说来，我的想法还是成立的，可以达到提高squid命中与效率，增大缓存容量的作用