<a href="http://surpass-li.javaeye.com/blog/253052">http://surpass-li.javaeye.com/blog/253052</a>
關鍵字: squid web加速
測試環境：
作業系統:centos 5.0
Web 伺服器: apache2 + tomcat 5.5
Jdk : j2se 1.5.5
1. 下載下傳squid-3.0.STABLE9.tar.gz （測試時最新的版本）。
http://www.squid-cache.org/Versions/v3/3.0/squid-3.0.STABLE9.tar.gz
2. 添加使用者及組
# useradd squid -M -c "Squid user" -d /dev/null -s /sbin/nologin
3. 解壓并編譯安裝
tar squid-3.0.STABLE9.tar.gz
cd squid-3.0.STABLE9
./configure --prefix=/data/squid3 --disable-carp --with-aufs-threads=32 --with-pthreads --enable-storeio='ufs,aufs, null' --enable-disk-io='AIO,Blocking' --enable-removal-policies='heap,lru' --disable-wccp --enable-kill-parent-hack --disable-snmp --disable-poll --disable-select --enable-auth=basic --with-aio --disable-ident-lookup --with-filedescriptors=65536
編譯參數不做詳細介紹請查相關文檔
Make
make install
安裝完畢。
4. 配置
可能需要建立一些檔案這些都是配置檔案中需要調用的（這個要注意檔案的屬主和權限）
1) [root@www ~]#cd /data/squid3/var/logs/
2) [root@www ~]#touch cache.log
3) [root@www ~]#chmod 755 cache.log
4) [root@www ~]#chown squid:squid cache.log
5) [root@www ~]#touch page_zs_access_log
6) [root@www ~]#chmod 755 page_zs_access_log
7) [root@www ~]#chown squid:squid page_zs_access_log
8) [root@www ~]#cd /data/squid3/etc/
9) 配置squid 配置檔案 squid.conf
[root@www ~]# vi squid.conf (192.168.3.11 為伺服器的ip 位址)
visible_hostname www.test.com
http_port 80 vhost vport
cache_mem 512 MB
maximum_object_size_in_memory 2048 KB
memory_replacement_policy lru
cache_dir ufs /tmp 512 16 256
max_open_disk_fds 0
minimum_object_size 0 KB
maximum_object_size 32768 KB
logformat combined %>a %ui %un [%tl] "%rm %ru HTTP/%rv" %Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
access_log /data/squid3/var/logs/page_zs_access_log combined
pid_filename/data/squid3/var/logs/squid.pid
cache_store_log none
cache_peer 192.168.3.11 parent 81 0 no-query no-digest originserver name=www
cache_peer_domain www www.test.com
cache_peer_access www allow all
http_access allow all
acl QUERY urlpath_regex cgi-bin .php .cgi .avi .wmv .rm .ram .mpg .mpeg .zip .exe
cache deny QUERY
cache_effective_user squid
cache_effective_group squid
10) [root@www ~]#/data/squid3/sbin/squid -k parse
可以根據這個測試指令用來驗證squid.conf 的文法和配置（下面是OK 的如果不OK 會有相應的提示根據提示來修改配置檔案）
2008/10/14 21:14:56| Processing Configuration File: /data/squid3/etc/squid.conf (depth 0)
11) [root@www ~]#/data/squid3/sbin/squid -z
用來建立緩存目錄
12) vi 一個squid.sh 的啟動腳本如下：賦予可執行權限
[root@www ~]#vi squid.sh
#!/bin/sh
#
ulimit -HSn 15000
# this script starts and stops Squid
echo 15000 > /proc/sys/fs/file-max
case "$1" in
start)
/data/squid3/sbin/squid -s
echo -n ' Squid'
;;
stop)
/data/squid3/sbin/squid -k shutdown
esac
#chmod +x squid.sh
5. 啟動squid
[root@www ~]#./squid.sh start 就可以啟動squid 了
檢視有沒有啟動可以
[root@www ~]#ps fax|grep squid
13750 pts /3 S+ 0:00 /_ grep squid
30474 ? Ss 0:00 /data/squid3/sbin/squid -s
30476 ? S 0:01 /_ (squid) -s
通過指令lsof -i:80 檢視誰占用了80 端口
檢視squid 的通路日志。
[root@www ~]# tail – f /data/squid3/var/logs/page_zs_access_log
檢視命中率及其他相關資訊
[root@www ~]# /data/squid3/bin/squidclient -p 80 -h localhost mgr:info
HTTP/1.0 200 OK
Server: squid/3.0.STABLE9
Mime-Version: 1.0
Date: Tue, 14 Oct 2008 13:22:40 GMT
Content-Type: text/plain
Expires: Tue, 14 Oct 2008 13:22:40 GMT
Last-Modified: Tue, 14 Oct 2008 13:22:40 GMT
X-Cache: MISS from www.6558855.com
Via: 1.0 www.6558855.com (squid/3.0.STABLE9)
Connection: close
Squid Object Cache: Version 3.0.STABLE9
Start Time: Tue, 14 Oct 2008 11:25:50 GMT
Current Time: Tue, 14 Oct 2008 13:22:40 GMT
Connection information for squid:
Number of clients accessing cache: 2
Number of HTTP requests received: 772
Number of ICP messages received: 0
Number of ICP messages sent: 0
Number of queued ICP replies: 0
Number of HTCP messages received: 0
Number of HTCP messages sent: 0
Request failure ratio: 0.00
Average HTTP requests per minute since start: 6.6
Average ICP messages per minute since start: 0.0
Select loop called: 7081542 times, 0.990 ms avg
Cache information for squid:
Hits as % of all requests: 5min: 0.0%, 60min: 89.7%
Hits as % of bytes sent: 5min: -0.0%, 60min: -0.0%
Memory hits as % of hit requests: 5min: 0.0%, 60min: 0.0%
Disk hits as % of hit requests: 5min: 0.0%, 60min: 0.0%
Storage Swap size: 104 KB
Storage Swap capacity: 0.0% used, 100.0% free
Storage Mem size: 228 KB
Storage Mem capacity: 0.0% used, 100.0% free
Mean Object Size: 10.40 KB
Requests given to unlinkd: 68
Median Service Times (seconds) 5 min 60 min:
HTTP Requests (All): 0.00000 0.00000
Cache Misses: 0.00000 0.00000
Cache Hits: 0.00000 0.00000
Near Hits: 0.00000 0.00000
Not-Modified Replies: 0.00000 0.00000
DNS Lookups: 0.00000 0.00000
ICP Queries: 0.00000 0.00000
Resource usage for squid:
UP Time: 7009.125 seconds
CPU Time: 0.948 seconds
CPU Usage: 0.01%
CPU Usage, 5 minute avg: 0.00%
CPU Usage, 60 minute avg: 0.01%
Process Data Segment Size via sbrk(): 2968 KB
Maximum Resident Size: 0 KB
Page faults with physical i/o: 2
Memory usage for squid via mallinfo():
Total space in arena: 3240 KB
Ordinary blocks: 3194 KB 17 blks
Small blocks: 0 KB 0 blks
Holding blocks: 11472 KB 17 blks
Free Small blocks: 0 KB
Free Ordinary blocks: 45 KB
Total in use: 14666 KB 100%
Total free: 45 KB 0%
Total size: 14712 KB
Memory accounted for:
Total accounted: 3001 KB 20%
memPool accounted: 3001 KB 20%
memPool unaccounted: 11710 KB 80%
memPoolAlloc calls: 147106
memPoolFree calls: 145713
File descriptor usage for squid:
Maximum number of file descriptors: 15000
Largest file desc currently in use: 14
Number of file desc currently in use: 8
Files queued for open: 0
Available number of file descriptors: 14992
Reserved number of file descriptors: 100
Store Disk files open: 0
Internal Data Structures:
45 StoreEntries
41 StoreEntries with MemObjects
40 Hot Object Cache Items
10 on-disk objects
6. 關于動态頁面的緩存。
如 jsp 頁面。
利用Header 為jsp 伺服器減壓
在參與緩存的jsp 中加入如下程式，進行“Last-Modified ”和“Expires ”的設定；
<%@ page import="java.io.*"%>
<%
long file_lmodified = new File("/tmp/catchmodified".lastModified();
response.setBufferSize(16);
response.setDateHeader("Last-Modified", file_lmodified);
response.setDateHeader("Expires", System.currentTimeMillis() / 1000 * 1000 + 300000);
response.flushBuffer();
%>
7. 添加自動更新記時方式
[root@www ~]# vi refreshCatch.sh
#/bin/sh
/bin/echo >/tmp/catchmodified
Chmod +x refreshCatch.sh
然後在crontab 裡寫一句
*/5 * * * * /data/squid3/refreshCatch.sh
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