Lighttpd是另外一种低内存占用率服务器,其性能卓异,而且稳定、灵活、高速。Lighttpd由Jan Kneschke开发,2003年发布。其CPU负载低,一大特色是应用了速度优化技术。Lighttpd对于那些饱受负载过高之苦的地方而言无异于雪中送炭。根据Netcraft公司2011年三月市场调查显示,Lighttpd目前排名第五,是YouTube、The Pirate Bay和Meebo等网站的首选网络服务器。
Lighttpd 是一个德国人领导的开源Web服务器软件,其根本的目的是提供一个专门针对高性能网站,安全、快速、兼容性好并且灵活的web server环境。具有非常低的内存开销、cpu占用率低、效能好以及丰富的模块等特点。
Lighttpd是众多OpenSource轻量级的web server中较为优秀的一个。支持FastCGI,CGI,Auth,输出压缩(output compress),URL重写,Alias等重要功能;而Apache之所以流行,很大程度也是因为功能丰富,在lighttpd上很多功能都有相应的实现了,这点对于apache的用户是非常重要的,因为迁移到lighttpd就必须面对这些问题。
特点:
相较于其他的网页服务器,lighttpd仅需少量的内存及CPU资源即可达到同样的效能。
lighttpd
Lighttpd是一个具有非常低的内存开销,cpu占用率低,效能好,以及丰富的模块等特点。lighttpd是众多OpenSource轻量级的web server中较为优秀的一个。支持FastCGI, CGI, Auth, 输出压缩(output compress), URL重写, Alias等重要功能。
Lighttpd使用fastcgi方式运行php,它会使用很少的PHP进程响应很大的并发量。
Fastcgi的优点在于:
从稳定性上看, fastcgi是以独立的进程池运行来cgi,单独一个进程死掉,系统可以很轻易的丢弃,然后重新分配新的进程来运行逻辑.
从安全性上看, fastcgi和宿主的server完全独立, fastcgi怎么down也不会把server搞垮,
从性能上看, fastcgi把动态逻辑的处理从server中分离出来, 大负荷的IO处理还是留给宿主server, 这样宿主server可以一心一意作IO,对于一个普通的动态网页来说, 逻辑处理可能只有一小部分, 大量的图片等静态IO处理完全不需要逻辑程序的参与(注1)
从扩展性上讲, fastcgi是一个中立的技术标准, 完全可以支持任何语言写的处理程序(php,java,python...)
nginx与lighttpd性能简单对比
做nginx和lighttpd的性能对比,可以在选择webserver上做个参考。
测试环境如下
Dell2950 4G内存,FreeBSD 8.2 release
#sysctl -a | grep CPU
hw.model: Intel(R) Xeon(R) CPU 5130 @ 2.00GHz
2x2颗
内存4G
#uname -a
FreeBSD localhost.localdomain 8.2-RELEASE
php5.2.17,fastcgi方式,默认5进程测试,失败请求太多,改用20进程,无请求失败。
Nginx主要配置
events {
use kqueue;
worker_connections 102400;
}
写了个phpinfo用ab测试,内网IP,不考虑带宽因素。
# ab -n 100000 -c 1000 http://192.168.100.28/info.php
This is ApacheBench, Version 1.3d <$Revision: 1.73 $> apache-1.3
Copyright (c) 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Copyright (c) 2006 The Apache Software Foundation, http://www.apache.org/
Benchmarking 192.168.100.28 (be patient)
Completed 10000 requests
Completed 20000 requests
Completed 30000 requests
Completed 40000 requests
Completed 50000 requests
Completed 60000 requests
Completed 70000 requests
Completed 80000 requests
Completed 90000 requests
Finished 100000 requests
Server Software: nginx/1.0.0
Server Hostname: 192.168.100.28
Server Port: 80
Document Path: /info.php
Document Length: 49457 bytes
Concurrency Level: 1000
Time taken for tests: 86.578 seconds
Complete requests: 100000
Failed requests: 0
Broken pipe errors: 0
Total transferred: 4977355920 bytes
HTML transferred: 4961202790 bytes
Requests per second: 1155.03 [#/sec] (mean)
Time per request: 865.78 [ms] (mean)
Time per request: 0.87 [ms] (mean, across all concurrent requests)
Transfer rate: 57489.84 [Kbytes/sec] received
Connnection Times (ms)
min mean[+/-sd] median max
Connect: 0 297 888.8 11 6414
Processing: 20 555 649.9 421 9989
Waiting: 18 555 649.9 421 9988
Total: 20 852 1065.3 473 10222
Percentage of the requests served within a certain time (ms)
50% 473
66% 584
75% 699
80% 776
90% 3308
95% 3473
98% 3688
99% 3817
100% 10222 (last request)
iostat -w 1
tty mfid0 da0 cd0 cpu
tin tout KB/t tps MB/s KB/t tps MB/s KB/t tps MB/s us ni sy in id
0 23 19.12 1 0.01 0.01 0 0.00 0.00 0 0.00 0 0 0 0 100
0 235 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 0 0 0 0 100
0 79 2.00 3 0.01 0.00 0 0.00 0.00 0 0.00 0 0 0 0 100
4 393 2.00 2 0.00 0.00 0 0.00 0.00 0 0.00 10 0 4 2 85
0 78 123.85 54 6.52 0.00 0 0.00 0.00 0 0.00 76 0 17 7 0
0 76 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 72 0 16 8 5
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 81 0 12 5 2
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 74 0 15 7 3
0 79 16.95 19 0.31 0.00 0 0.00 0.00 0 0.00 71 0 19 8 2
0 78 21.60 10 0.21 0.00 0 0.00 0.00 0 0.00 74 0 17 7 2
0 78 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 74 0 17 8 1
0 78 53.33 3 0.16 0.00 0 0.00 0.00 0 0.00 68 0 21 10 1
0 104 20.20 20 0.39 0.00 0 0.00 0.00 0 0.00 68 0 18 10 5
磁盘压力只在测试开始时大,并且因为所有东西都放在一台服务器,瞬间最高把CPU空闲率干到了0.3%,但实际上占用CPU最多的是ab,占了40%多,nginx占用不到40%
------------------------------------------------换lighttpd
server.max-fds = 8192
##
## Stat() call caching.
##
## lighttpd can utilize FAM/Gamin to cache stat call.
##
## possible values are:
## disable, simple or fam.
##
server.stat-cache-engine = "simple"
##
## Fine tuning for the request handling
##
## max-connections == max-fds/2 (maybe /3)
## means the other file handles are used for fastcgi/files
##
Server.max-connections = 4096
也是使用kqueue队列
# ab -n 100000 -c 1000 http://192.168.100.28/info.php
This is ApacheBench, Version 1.3d <$Revision: 1.73 $> apache-1.3
Copyright (c) 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Copyright (c) 2006 The Apache Software Foundation, http://www.apache.org/
Benchmarking 192.168.100.28 (be patient)
Completed 10000 requests
Completed 20000 requests
Completed 30000 requests
Completed 40000 requests
Completed 50000 requests
Completed 60000 requests
Completed 70000 requests
Completed 80000 requests
Completed 90000 requests
Finished 100000 requests
Server Software: lighttpd/1.4.28
Server Hostname: 192.168.100.28
Server Port: 80
Document Path: /info.php
Document Length: 49127 bytes
Concurrency Level: 1000
Time taken for tests: 83.107 seconds
Complete requests: 100000
Failed requests: 0
Broken pipe errors: 0
Total transferred: 4932575365 bytes
HTML transferred: 4915304142 bytes
Requests per second: 1203.27 [#/sec] (mean)
Time per request: 831.07 [ms] (mean)
Time per request: 0.83 [ms] (mean, across all concurrent requests)
Transfer rate: 59352.10 [Kbytes/sec] received
Connnection Times (ms)
min mean[+/-sd] median max
Connect: 0 19 206.2 1 3113
Processing: 79 807 155.8 823 3891
Waiting: 66 807 155.8 823 3890
Total: 79 826 251.0 826 4248
Percentage of the requests served within a certain time (ms)
50% 826
66% 843
75% 854
80% 862
90% 894
95% 939
98% 1006
99% 1094
100% 4248 (last request)
# iostat -w 1
tty mfid0 da0 cd0 cpu
tin tout KB/t tps MB/s KB/t tps MB/s KB/t tps MB/s us ni sy in id
0 23 19.25 1 0.01 0.01 0 0.00 0.00 0 0.00 0 0 0 0 100
0 387 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 0 0 0 0 99
0 78 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 0 0 0 0 100
4 2185 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 47 0 14 7 33
0 78 120.00 2 0.23 0.00 0 0.00 0.00 0 0.00 68 0 23 9 1
0 2405 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 77 0 14 6 2
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 71 0 17 10 2
0 1852 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 72 0 18 8 2
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 62 0 22 7 10
0 1143 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 68 0 20 9 3
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 65 0 25 8 2
0 2074 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 69 0 22 8 2
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 65 0 23 10 3
0 1917 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 62 0 26 10 3
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 63 0 25 8 5
0 2247 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 66 0 23 8 3
0 79 128.00 1 0.12 0.00 0 0.00 0.00 0 0.00 66 0 25 7 2
0 1373 48.00 7 0.33 0.00 0 0.00 0.00 0 0.00 66 0 22 8 4
看起来,lighttpd在磁盘上并没有nginx那样的瞬间压力。
总结:
一开始的失败请求主要来自php-cgi,在此服务器上,默认进程数无法处理大并发访问量。改为20以上就不存在失败了,再高收益不大。从高负载动态页面吞吐率上说,lighttpd可能要稍稍高于nginx。
附ab静态页面吞吐率
lighttpd Requests per second: 9045.68 [#/sec] (mean)
nginx Requests per second: 11622.50 [#/sec] (mean)
处理静态页面上,nginx要比lighttpd快不少。如果去掉ab对cpu的压力,两款软件加php对cpu的压力应该不超过70%。
在处理诸如php,ror等应用方面的极端压榨,可以考虑使用lighttpd。处理静态页面可以考虑使用nginx。篇幅有限,vmstat和truss跟踪的结果就不贴了。