Apache bench marking tool to identify the HTTP server performance along with AEM server Load Testing

Solution:

• ab is a tool for benchmarking your Apache Hypertext Transfer Protocol (HTTP) server.
• It is designed to give you an impression of how your current Apache installation performs.
• This especially shows you how many requests per second your Apache installation is capable of serving.
• To minimize the impact of garbage collection, etc, it is recommended to use a tool such as apachebench
• To help identify memory leaks and selectively analyze response time.

Apache Bench can be used in the following way:
$ ab -c 5 -k -n 1000 "http://localhost:4503/content/geometrixx/en/company.html"

this is ApacheBench, Version 2.3 <$Revision: 655654 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/

Licensed to The Apache Software Foundation, http://www.apache.org/T

Benchmarking localhost (be patient)
Completed 100 requests
Completed 200 requests
Completed 300 requests
Completed 400 requests
Completed 500 requests
Completed 600 requests
Completed 700 requests
Completed 800 requests
Completed 900 requests
Completed 1000 requests
Finished 1000 requests

Server Software: Day-Servlet-Engine/4.1.52
Server Hostname: localhost
Server Port: 4503

Document Path: /content/geometrixx/en/company.html
Document Length: 24127 bytes

Concurrency Level: 5
Time taken for tests: 69.766 seconds
Complete requests: 1000
Failed requests: 998
(Connect: 0, Receive: 0, Length: 998, Exceptions: 0)
Write errors: 0
Keep-Alive requests: 0
Total transferred: 24160923 bytes
HTML transferred: 24010923 bytes
Requests per second: 14.33 /sec (mean)
Time per request: 348.828 [ms] (mean)
Time per request: 69.766 [ms] (mean, across all concurrent requests)
Transfer rate: 338.20 [Kbytes/sec] received

Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 1 3.9 0 58
Processing: 138 347 568.5 282 8106
Waiting: 137 344 568.1 281 8106
Total: 139 348 568.4 283 8106

Percentage of the requests served within a certain time (ms)
50% 283
66% 323
75% 356
80% 374
90% 439
95% 512
98% 1047
99% 1132
100% 8106 (longest request)

apachebench also displays the time per request as the mean, across all concurrent requests; see Time per request: 54.595 [ms] (mean, across all concurrent requests).
You can change the value of the concurrency parameter -c(number of multiple requests to perform at a time) to see any effects.

Command details :
-c concurrencyNumber of multiple requests to perform at a time.
Default is one request at a time. -kEnable the HTTP KeepAlive feature, i.e., perform multiple requests within one HTTP session. Default is no KeepAlive. -n requestsNumber of requests to perform for the benchmarking session. The default is to just perform a single request which usually leads to non-representative benchmarking results.

Reference: http://httpd.apache.org/docs/2.2/programs/ab.html