nginx机器配置：

     CPU：     E7500  @ 2.93GHz (双核)

     内存：4G

     varnish机器配置：

     CPU：     E3300  @ 2.50GHz (双核)

     内存：2G

     测试脚本执行机器配置：

     CPU：     AMD Phenom(tm) II X4 925 Processor

     内存：2G

    2.1：安装siege

    使用压力测试工具siege(http://www.joedog.org/index/siege-home) 来验证。可以根据路径来并发重复压力测试。安装方式：

     下载：wget ftp://sid.joedog.org/pub/siege/siege-latest.tar.gz

     安装：

     #./configure

     #make && make install

[root@localhost test] siege -c 100 -r 100 -f varnish_url.txt
[root@localhost test] siege -c 100 -r 100 -f nginx_url.txt

    参数说明：

     -c 100 并发100个用户

     -r 100 重复循环100次

     -f varnish_url.txt 任务列表：URL列表

    2.2：构造URL

     构造了536个url测试，其中1个是错误的url。

    到测试机器上,

[root@localhost test] cd /data/htdocs/resources/web
[root@localhost test] find . -name "*.jpg" -print > varnish_url.txt

    2.3：开启nginx图片缓存方法

     开启nginx的缓存图片的方法，在nginx的conf中添加：

location ~ .*\\.(gif|jpg|jpeg|png|bmp|swf|ico)$ {
    expires      30d;
    access_log   off;
}

    3.1.1：nginx不带缓存的情况

    Transactions:                  10000 hits

     Availability:                 100.00 %

     Elapsed time:                  65.83 secs

     Data transferred:             260.83 MB

     Response time:                  0.01 secs

     Transaction rate:             151.91 trans/sec

     Throughput:                     3.96 MB/sec

     Concurrency:                    2.06

     Successful transactions:        9900

     Failed transactions:               0

     Longest transaction:            3.03

     Shortest transaction:           0.00

    3.1.2：nginx带缓存的情况

     Transactions:                  10000 hits

     Availability:                 100.00 %

     Elapsed time:                  63.90 secs

     Data transferred:             266.10 MB

     Response time:                  0.01 secs

     Transaction rate:             156.49 trans/sec

     Throughput:                     4.16 MB/sec

     Concurrency:                    2.18

     Successful transactions:        9900

     Failed transactions:               0

     Longest transaction:            0.35

     Shortest transaction:           0.00

    3.1.3：nginx带缓存第二次测试的情况

     Transactions:                  10000 hits

     Availability:                 100.00 %

     Elapsed time:                  63.05 secs

     Data transferred:             266.10 MB

     Response time:                  0.01 secs

     Transaction rate:             158.60 trans/sec

     Throughput:                     4.22 MB/sec

     Concurrency:                    2.06

     Successful transactions:        9900

     Failed transactions:               0

     Longest transaction:            0.34

     Shortest transaction:           0.00

    3.2.1：varnish清空缓存第一次测试情况

     Transactions:                  10000 hits

     Availability:                 100.00 %

     Elapsed time:                  62.87 secs

     Data transferred:             266.10 MB

     Response time:                  0.01 secs

     Transaction rate:             159.06 trans/sec

     Throughput:                     4.23 MB/sec

     Concurrency:                    1.95

     Successful transactions:        9900

     Failed transactions:               0

     Longest transaction:            0.37

     Shortest transaction:           0.00

    3.2.2：varnish有缓存测试

     Transactions:                  10000 hits

     Availability:                 100.00 %

     Elapsed time:                  61.91 secs

     Data transferred:             266.10 MB

     Response time:                  0.01 secs

     Transaction rate:             161.52 trans/sec

     Throughput:                     4.30 MB/sec

     Concurrency:                    1.78

     Successful transactions:        9900

     Failed transactions:               0

     Longest transaction:            0.34

     Shortest transaction:           0.00

    3.2.3：varnish负责均衡性能

     Transactions:                  10000 hits

     Availability:                 100.00 %

     Elapsed time:                  59.75 secs

     Data transferred:             266.10 MB

     Response time:                  0.01 secs

     Transaction rate:             167.36 trans/sec

     Throughput:                     4.45 MB/sec

     Concurrency:                    1.98

     Successful transactions:        9900

     Failed transactions:               0

     Longest transaction:            3.01

     Shortest transaction:           0.00