📅 最后修改于: 2020-12-07 04:26:34 🧑 作者: Mango
在本章中，我们将比较带有和不带有标志的输出。让我们看看使用适当的标志如何提高Web应用程序的性能。在此之前，我们需要了解如果您的应用程序很简单，那么您可能不会注意到其中的区别。与我们简单的应用程序一样(带有标志和不带有标志)。然后，我们将使用https://www.apache.org/ URL执行相同的测试，并观察其中的区别。
在本节中，我们将了解如何在没有标志的情况下测试我们的应用程序。
$ ab -n 100 -c 10 http://127.0.0.1:8000/
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 127.0.0.1 (be patient).....done
Server Software: Rocket
Server Hostname: 127.0.0.1
Server Port: 8000
Document Path: /
Document Length: Variable
Concurrency Level: 10
Time taken for tests: 0.244 seconds
Complete requests: 100
Failed requests: 0
Non-2xx responses: 100
Keep-Alive requests: 0
Total transferred: 27700 bytes
HTML transferred: 6600 bytes
Requests per second: 2208.77 [#/sec] (mean)
Time per request: 4.527 [ms] (mean)
Time per request: 0.453 [ms] (mean, across all concurrent requests)
Transfer rate: 597.49 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 1 2 0.7 2 3
Processing: 0 2 0.7 2 4
Waiting: 0 2 1.0 2 3
Total: 4 4 0.3 4 5
Percentage of the requests served within a certain time (ms)
50% 4
66% 4
75% 5
80% 5
90% 5
95% 5
98% 5
99% 5
100% 5 (longest request)
在本节中，我们将了解如何使用标志来测试我们的应用程序。
$ ab -l -r -n 100 -c 10 -k -H "Accept-Encoding: gzip, deflate" http://127.0.0.1:8000/
...
Requests per second: 2277.07 [#/sec] (mean)
Time per request: 4.392 [ms] (mean)
Time per request: 0.439 [ms] (mean, across all concurrent requests)
Transfer rate: 615.97 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 1 2 0.7 2 3
Processing: 0 2 0.7 2 4
Waiting: 0 2 1.0 2 3
Total: 4 4 0.2 4 5
Percentage of the requests served within a certain time (ms)
50% 4
66% 4
75% 4
80% 4
90% 5
95% 5
98% 5
99% 5
100% 5 (longest request)
我们可以简单地注意到，输出统计信息之间并没有太大的区别。
现在让我们看看如何测试不带标志的Apache Organization网站。
$ ab -n 100 -c 10 http://www.apache.org/
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 www.apache.org (be patient).....done
Server Software: Apache/2.4.7
Server Hostname: www.apache.org
Server Port: 80
Document Path: /
Document Length: 58433 bytes
Concurrency Level: 10
Time taken for tests: 1.498 seconds
Complete requests: 100
Failed requests: 0
Total transferred: 5877500 bytes
HTML transferred: 5843300 bytes
Requests per second: 66.74 [#/sec] (mean)
Time per request: 149.840 [ms] (mean)
Time per request: 14.984 [ms] (mean, across all concurrent requests)
Transfer rate: 3830.58 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 12 110 295.2 12 1012
Processing: 37 38 0.5 38 39
Waiting: 12 13 0.3 13 15
Total: 49 147 295.4 50 1051
Percentage of the requests served within a certain time (ms)
50% 50
66% 50
75% 50
80% 50
90% 816
95% 1050
98% 1051
99% 1051
100% 1051 (longest request)
现在让我们使用Flags测试Apache组织网站。
$ ab -l -r -n 100 -c 10 -k -H "Accept-Encoding: gzip, deflate" http://www.apache.org/
...
Document Length: Variable
Concurrency Level: 10
Time taken for tests: 0.357 seconds
Complete requests: 100
Failed requests: 0
Keep-Alive requests: 100
Total transferred: 1358510 bytes
HTML transferred: 1317700 bytes
Requests per second: 280.28 [#/sec] (mean)
Time per request: 35.678 [ms] (mean)
Time per request: 3.568 [ms] (mean, across all concurrent requests)
Transfer rate: 3718.41 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 1 3.7 0 12
Processing: 14 17 21.3 15 227
Waiting: 14 17 21.3 14 227
Total: 14 18 21.5 15 227
Percentage of the requests served within a certain time (ms)
50% 15
66% 15
75% 15
80% 15
90% 27
95% 28
98% 29
99% 227
100% 227 (longest request)
您可以简单地注意到每秒使用标志如何增加请求。在当前情况下，这尤其是由于使用-H“ Accept-Encoding：gzip ，deflate，因为此标志告诉Apache服务器以gzip格式处理请求。
在涉及Apache Bench结果时，需要考虑一些重要点。这将帮助我们设计总体策略，以消除应用程序中的瓶颈并提高其性能。
我们需要每秒请求。这使我们了解了Web服务器设置的运行状况。数字越大，性能越好。然后是连接时间(ms)和所服务请求的百分比。您可能需要调整Web服务器的设置，才能将这些指标更改为所需的性能。
检查Apache或使用的Web服务器错误日志或(常规)日志中是否有错误。随着您增加负载，事情将开始窒息：内存问题将开始出现。如果不考虑并发性，许多Python脚本将开始崩溃。
您需要找出关键的并发值是多少，超过该值，Web服务器将崩溃和/或超时?通常，这应该在相当高的并发级别上发生。如果此值较低，则说明出现了问题，您需要将这些设置调低/调高。
在本教程中，我们学习了如何使用Apache Bench来对任何网站或Web应用程序进行负载测试。 Apache Bench是一个非常有价值的工具，可用于确定应如何改进Web应用程序服务器设置，减少瓶颈并提高性能。现在您已熟悉Apache Bench的基本用法，您可以从创建新的测试计划开始，以衡量各种情况下应用程序的性能。