简介

压测工具有很多，如：LoadRunner、JMeter、ab等
LoadRunner和JMeter使用相对复杂，ab比较简单

ab是Apache附带的压测软件

➜  ~ ab -V
This is ApacheBench, Version 2.3 <$Revision: 1826891 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/

ab 参数

➜  ~ ab -h
Usage: ab [options] [http[s]://]hostname[:port]/path
Options are:
    -n requests     Number of requests to perform
    -c concurrency  Number of multiple requests to make at a time
    -t timelimit    Seconds to max. to spend on benchmarking
                    This implies -n 50000
    -s timeout      Seconds to max. wait for each response
                    Default is 30 seconds
    -b windowsize   Size of TCP send/receive buffer, in bytes
    -B address      Address to bind to when making outgoing connections
    -p postfile     File containing data to POST. Remember also to set -T
    -u putfile      File containing data to PUT. Remember also to set -T
    -T content-type Content-type header to use for POST/PUT data, eg.
                    'application/x-www-form-urlencoded'
                    Default is 'text/plain'
    -v verbosity    How much troubleshooting info to print
    -w              Print out results in HTML tables
    -i              Use HEAD instead of GET
    -x attributes   String to insert as table attributes
    -y attributes   String to insert as tr attributes
    -z attributes   String to insert as td or th attributes
    -C attribute    Add cookie, eg. 'Apache=1234'. (repeatable)
    -H attribute    Add Arbitrary header line, eg. 'Accept-Encoding: gzip'
                    Inserted after all normal header lines. (repeatable)
    -A attribute    Add Basic WWW Authentication, the attributes
                    are a colon separated username and password.
    -P attribute    Add Basic Proxy Authentication, the attributes
                    are a colon separated username and password.
    -X proxy:port   Proxyserver and port number to use
    -V              Print version number and exit
    -k              Use HTTP KeepAlive feature
    -d              Do not show percentiles served table.
    -S              Do not show confidence estimators and warnings.
    -q              Do not show progress when doing more than 150 requests
    -l              Accept variable document length (use this for dynamic pages)
    -g filename     Output collected data to gnuplot format file.
    -e filename     Output CSV file with percentages served
    -r              Don't exit on socket receive errors.
    -m method       Method name
    -h              Display usage information (this message)
    -I              Disable TLS Server Name Indication (SNI) extension
    -Z ciphersuite  Specify SSL/TLS cipher suite (See openssl ciphers)
    -f protocol     Specify SSL/TLS protocol
                    (TLS1, TLS1.1, TLS1.2 or ALL)

ab常用命令

  • -n：测试会话中执行的请求数，默认1
  • -c：要创建的用户数，默认1
  • -t：等待web服务器响应的最大时间（单位：s），默认没有时间限制
  • -k：使用Keep-Alive特性
  • -c：对一个请求附加一个Cookie，形式name=value

测试

➜  ~ ab -c10 -n1000 http://test.local/
This is ApacheBench, Version 2.3 <$Revision: 1826891 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/

Benchmarking test.local (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:        nginx/1.13.12
Server Hostname:        test.local
Server Port:            80

Document Path:          /
Document Length:        1579 bytes

Concurrency Level:      10
Time taken for tests:   15.035 seconds
Complete requests:      1000
Failed requests:        0
Total transferred:      1743000 bytes
HTML transferred:       1579000 bytes
Requests per second:    66.51 [#/sec] (mean)
Time per request:       150.347 [ms] (mean)
Time per request:       15.035 [ms] (mean, across all concurrent requests)
Transfer rate:          113.21 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.4      0      13
Processing:     5  117 216.9     41    3156
Waiting:        5  116 211.8     41    3079
Total:          6  117 217.0     41    3156

Percentage of the requests served within a certain time (ms)
  50%     41
  66%    111
  75%    160
  80%    202
  90%    281
  95%    348
  98%    755
  99%   1461
 100%   3156 (longest request)

重点关注几个参数

Requests per second：吞吐率
Time taken for tests：请求用时

使用长连接-k，明显可以看到请求时间减少了很多，吞吐率也提高了很多

➜  ~ ab -c10 -n1000 -k http://test.local/
Concurrency Level:      10
Time taken for tests:   1.081 seconds
Complete requests:      1000
Failed requests:        0
Keep-Alive requests:    0
Total transferred:      1743000 bytes
HTML transferred:       1579000 bytes
Requests per second:    925.44 [#/sec] (mean)
Time per request:       10.806 [ms] (mean)
Time per request:       1.081 [ms] (mean, across all concurrent requests)
Transfer rate:          1575.24 [Kbytes/sec] received