***********安裝xcache，爲php加速*******************
unzip -o PHPMyAdmin-4.0.5-all-languages.zip
mv PHPMyAdmin-4.0.5-all-languages /usr/local/apache/htdocs/pma
1，壓力測試：
ulimit -n 3000
ab -c 100 -n 2000 http://10.10.37.138/pma/index.php 十個併發，發兩千個請求
[root@localhost local]# ulimit -n 3000
[root@localhost local]# ab -c 100 -n 2000 http://10.10.37.138/pma/index.php
This is ApacheBench, Version 2.3 <$Revision: 1554214 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/
Benchmarking 10.10.37.138 (be patient)
Completed 200 requests
Completed 400 requests
Completed 600 requests
Completed 800 requests
Completed 1000 requests
Completed 1200 requests
Completed 1400 requests
Completed 1600 requests
Completed 1800 requests
Completed 2000 requests
Finished 2000 requests
Server Software: Apache/2.4.9 服務器軟件版本
Server Hostname: 10.10.37.138 請求的服務器地址
Server Port: 80 服務器端口
Document Path: /pma/index.php
Document Length: 7794 bytes URL的大小
Concurrency Level: 100 併發請求
Time taken for tests: 103.874 seconds 整個測試經過的時長
Complete requests: 2000 一共2000的請求
Failed requests: 0
Total transferred: 17925162 bytes 包含首部和數據
HTML transferred: 15588000 bytes 總共傳輸的數據
Requests per second: 19.25 [#/sec] (mean) 每秒鐘完成的請求數
Time per request: 5193.681 [ms] (mean) 每一批(100個)請求需要的時間
Time per request: 51.937 [ms] (mean, across all concurrent requests) 每一個請求消耗的時間
Transfer rate: 168.52 [Kbytes/sec] received 傳輸速率
Connection Times (ms) 連接時間
min mean[+/-sd] median max
Connect: 0 11 58.9 0 497 連接建立
Processing: 2445 5139 1298.0 4850 17286 請求處理
Waiting: 2445 5111 1303.1 4820 17285 等待數據從磁盤加載完成並相應
Total: 2445 5150 1301.4 4858 17286
Percentage of the requests served within a certain time (ms)
50% 4858
66% 5165
75% 5410
80% 5590
90% 6274
95% 7209
98% 9036
99% 11075
100% 17286 (longest request)
sync
2，下載xcache-3.1.2.tar.bz2 百度搜索即可
解壓解包並編譯安裝
[root@localhost php]# man -M man/ phpize
/usr/local/php/bin/phpize 編譯第三方擴展是都需要執行
./configure --enable-xcache --with-php-config=/usr/local/php/bin/php-config
make && make install
安裝結束後會出現如下信息：
Installing shared extensions: /usr/local/php/lib/php/extensions/no-debug-zts-20100525/
3，配置：
[root@localhost xcache-3.1.2]# mkdir /etc/php.d
[root@localhost xcache-3.1.2]# cp xcache.ini /etc/php.d/
[root@localhost xcache-3.1.2]# vi /etc/php.d/xcache.ini
extension = /usr/local/php/lib/php/extensions/no-debug-zts-20100525/
4，再做壓力測試：
http://10.10.37.138/pma/index.php 刷新幾次生成緩存
再執行測試
ab -c 100 -n 2000 http://10.10.37.138/pma/index.php
Requests per second: 80.13 [#/sec] (mean)
Time per request: 1248.033 [ms] (mean)
Time per request: 12.480 [ms] (mean, across all concurrent requests)
安裝xcache之前的速度
Requests per second: 19.25 [#/sec] (mean)
Time per request: 5193.681 [ms] (mean)
Time per request: 51.937 [ms] (mean, across all concurrent requests)
速度上能快三倍多
Requests per second: 21.97 [#/sec] (mean)
Time per request: 4552.375 [ms] (mean)
Time per request: 45.524 [ms] (mean, across all concurrent requests)
適用於讀的多，寫的少的服務器類型