目前我安装的 Homestead 虚拟机版本是 2.1.8：
该版本 Homestead 上预装的 PHP 版本是 5.6.15：
我们使用 ab 命令（Apache 提供的性能测试工具）在该版本中测试 Laravel 应用（以目前正在讲的使用Laravel开发的博客应用为例）性能，我们模拟 10000 次请求，100 个并发进行压力测试：
ab -n 10000 -c 100 http://blog.app/
运行结果如下：
This is ApacheBench,Version 2.3
Copyright 1996 Adam Twiss,Zeus Technology Ltd,http://www.zeustech.net/
Licensed to The Apache Software Foundation,http://www.apache.org/
Benchmarking blog.app (be patient)
Completed 1000 requests
Completed 2000 requests
Completed 3000 requests
Completed 4000 requests
Completed 5000 requests
Completed 6000 requests
Completed 7000 requests
Completed 8000 requests
Completed 9000 requests
Completed 10000 requests
Finished 10000 requests
Server Software: nginx/1.8.0
Server Hostname: blog.app
Server Port: 80
Document Path: /
Document Length: 324 bytes
Concurrency Level: 100
Time taken for tests: 69.354 seconds
Complete requests: 10000
Failed requests: 0
Total transferred: 19851388 bytes
HTML transferred: 10230000 bytes
Requests per second: 144.19 [#/sec] (mean)
Time per request: 693.545 [ms] (mean)
Time per request: 6.935 [ms] (mean,across all concurrent requests)
Transfer rate: 279.52 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 0 0.2 0 3
Processing: 17 684 319.1 588 2720
Waiting: 17 684 319.1 588 2720
Total: 20 684 319.1 588 2720
Percentage of the requests served within a certain time (ms)
50% 588
66% 695
75% 842
80% 933
90% 1155
95% 1321
98% 1545
99% 1813
100% 2720 (longest request)
这里我们要关注的是红色加粗的文字，即每秒处理请求数，这是衡量系统性能的关键指标。根据系统及硬件配置的差异，数据会有些出入。
现在我们按照“Laravel Homestead 支持 PHP 7 ”这一节所述将 Homestead 中的 PHP 升级到 7.0 版本。
使用 vagrant ssh 登录到新添加的 homestead-7 虚拟机，查看 PHP 版本信息是否正确：
此时在浏览器中访问 http://blog.app 会报错，因为新安装的 Homestead 数据库数据为空，需要登录到虚拟机运行如下命令运行迁移并填充数据：
php artisan migrate php artisan db:seed
再次访问就OK了，好了我们继续使用同样的 ab 命令进行压力测试：
ab -n 10000 -c 100 http://blog.app/
运行结果如下：
This is ApacheBench,Version 2.3 Copyright 1996 Adam Twiss,http://www.zeustech.net/ Licensed to The Apache Software Foundation,http://www.apache.org/ Benchmarking blog.app (be patient) Completed 1000 requests Completed 2000 requests Completed 3000 requests Completed 4000 requests Completed 5000 requests Completed 6000 requests Completed 7000 requests Completed 8000 requests Completed 9000 requests Completed 10000 requests Finished 10000 requests Server Software: nginx/1.8.0 Server Hostname: blog.app Server Port: 80 Document Path: / Document Length: 324 bytes Concurrency Level: 100 Time taken for tests: 45.032 seconds Complete requests: 10000 Failed requests: 0 Total transferred: 20101202 bytes HTML transferred: 10230000 bytes Requests per second: 222.06 [#/sec] (mean) Time per request: 450.319 [ms] (mean) Time per request: 4.503 [ms] (mean,across all concurrent requests) Transfer rate: 435.91 [Kbytes/sec] received Connection Times (ms) min mean[+/-sd] median max Connect: 0 0 0.2 0 4 Processing: 11 443 252.8 379 1978 Waiting: 11 443 252.8 379 1978 Total: 15 443 252.8 379 1978 Percentage of the requests served within a certain time (ms) 50% 379 66% 517 75% 590 80% 631 90% 795 95% 938 98% 1060 99% 1229 100% 1978 (longest request)
经过对比，同一个 Laravel 应用在 PHP 7.0 下的性能比 PHP 5.6 提高了54%，这是一个很显著的性能提升，当然环境不同数据会有所出入，而且还有更大的提升空间。