man > ab

TLDR: ab (tldr-pages)

Apache HTTP server benchmarking tool.

  • Execute 100 HTTP GET requests to a given URL
    ab -n 100 {{url}}
  • Execute 100 HTTP GET requests, in concurrent batches of 10, to a URL
    ab -n 100 -c 10 {{url}}
  • Execute 100 HTTP POST requests to a URL, using a JSON payload from a file
    ab -n 100 -T {{application/json}} -p {{path/to/file.json}} {{url}}
  • Use HTTP keep-Alive, i.e. perform multiple requests within one HTTP session
    ab -k {{url}}
  • Set the maximum number of seconds (timeout) to spend for benchmarking (30 by default)
    ab -t {{60}} {{url}}
  • Write the results to a CSV file
    ab -e {{path/to/file.csv}}
AB(1)                                            ab                                            AB(1)

NAME
       ab - Apache HTTP server benchmarking tool


SYNOPSIS
       ab  [ -A auth-username:password ] [ -b windowsize ] [ -B local-address ] [ -c concurrency ] [
       -C cookie-name=value ] [ -d ] [ -e csv-file ] [ -E client-certificate file ] [ -f protocol  ]
       [  -g gnuplot-file ] [ -h ] [ -H custom-header ] [ -i ] [ -k ] [ -l ] [ -m HTTP-method ] [ -n
       requests ] [ -p POST-file ] [ -P proxy-auth-username:password ] [ -q ] [ -r ] [ -s timeout  ]
       [  -S  ] [ -t timelimit ] [ -T content-type ] [ -u PUT-file ] [ -v verbosity] [ -V ] [ -w ] [
       -x <table>-attributes ] [ -X proxy[:port] ] [ -y <tr>-attributes ] [ -z <td>-attributes  ]  [
       -Z ciphersuite ] [http[s]://]hostname[:port]/path



SUMMARY
       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 es‐
       pecially shows you how many requests per second your Apache installation is capable of  serv‐
       ing.



OPTIONS
       -A auth-username:password
              Supply  BASIC  Authentication credentials to the server. The username and password are
              separated by a single : and sent on the wire base64 encoded. The string  is  sent  re‐
              gardless of whether the server needs it (i.e., has sent an 401 authentication needed).

       -b windowsize
              Size of TCP send/receive buffer, in bytes.

       -B local-address
              Address to bind to when making outgoing connections.

       -c concurrency
              Number of multiple requests to perform at a time. Default is one request at a time.

       -C cookie-name=value
              Add  a  Cookie:  line  to  the  request.  The  argument  is typically in the form of a
              name=value pair. This field is repeatable.

       -d     Do not display the "percentage served within XX [ms] table". (legacy support).

       -e csv-file
              Write a Comma separated value (CSV) file which contains for each percentage  (from  1%
              to  100%) the time (in milliseconds) it took to serve that percentage of the requests.
              This is usually more useful than the  'gnuplot'  file;  as  the  results  are  already
              'binned'.

       -E client-certificate-file
              When  connecting  to an SSL website, use the provided client certificate in PEM format
              to authenticate with the server. The file is expected to contain the  client  certifi‐
              cate, followed by intermediate certificates, followed by the private key. Available in
              2.4.36 and later.

       -f protocol
              Specify SSL/TLS protocol (SSL2, SSL3, TLS1, TLS1.1, TLS1.2, or ALL). TLS1.1 and TLS1.2
              support available in 2.4.4 and later.

       -g gnuplot-file
              Write  all  measured values out as a 'gnuplot' or TSV (Tab separate values) file. This
              file can easily be imported into packages like Gnuplot, IDL, Mathematica, Igor or even
              Excel. The labels are on the first line of the file.

       -h     Display usage information.

       -H custom-header
              Append extra headers to the request. The argument is typically in the form of a  valid
              header  line,  containing  a colon-separated field-value pair (i.e., "Accept-Encoding:
              zip/zop;8bit").

       -i     Do HEAD requests instead of GET.

       -k     Enable the HTTP KeepAlive feature, i.e., perform multiple  requests  within  one  HTTP
              session. Default is no KeepAlive.

       -l     Do  not report errors if the length of the responses is not constant. This can be use‐
              ful for dynamic pages. Available in 2.4.7 and later.

       -m HTTP-method
              Custom HTTP method for the requests. Available in 2.4.10 and later.

       -n requests
              Number of requests to perform for the benchmarking session. The  default  is  to  just
              perform  a  single  request which usually leads to non-representative benchmarking re‐
              sults.

       -p POST-file
              File containing data to POST. Remember to also set -T.

       -P proxy-auth-username:password
              Supply BASIC Authentication credentials to a proxy en-route. The username and password
              are separated by a single : and sent on the wire base64 encoded. The  string  is  sent
              regardless  of  whether the proxy needs it (i.e., has sent an 407 proxy authentication
              needed).

       -q     When processing more than 150 requests, ab outputs a progress count  on  stderr  every
              10% or 100 requests or so. The -q flag will suppress these messages.

       -r     Don't exit on socket receive errors.

       -s timeout
              Maximum  number of seconds to wait before the socket times out. Default is 30 seconds.
              Available in 2.4.4 and later.

       -S     Do not display the median and standard deviation values, nor display the warning/error
              messages when the average and median are more than one or two times the standard devi‐
              ation apart. And default to the min/avg/max values. (legacy support).

       -t timelimit
              Maximum number of seconds to spend for benchmarking. This implies a  -n  50000  inter‐
              nally.  Use  this to benchmark the server within a fixed total amount of time. Per de‐
              fault there is no timelimit.

       -T content-type
              Content-type header to use for POST/PUT data,  eg.  application/x-www-form-urlencoded.
              Default is text/plain.

       -u PUT-file
              File containing data to PUT. Remember to also set -T.

       -v verbosity
              Set  verbosity  level  - 4 and above prints information on headers, 3 and above prints
              response codes (404, 200, etc.), 2 and above prints warnings and info.

       -V     Display version number and exit.

       -w     Print out results in HTML tables. Default table is two  columns  wide,  with  a  white
              background.

       -x <table>-attributes
              String to use as attributes for <table>. Attributes are inserted <table here >.

       -X proxy[:port]
              Use a proxy server for the requests.

       -y <tr>-attributes
              String to use as attributes for <tr>.

       -z <td>-attributes
              String to use as attributes for <td>.

       -Z ciphersuite
              Specify SSL/TLS cipher suite (See openssl ciphers)


OUTPUT
       The following list describes the values returned by ab:



       Server Software
              The  value,  if  any,  returned  in the server HTTP header of the first successful re‐
              sponse. This includes all characters in the header from beginning to the point a char‐
              acter with decimal value of 32 (most notably: a space or CR/LF) is detected.

       Server Hostname
              The DNS or IP address given on the command line

       Server Port
              The port to which ab is connecting. If no port is given on the command line, this will
              default to 80 for http and 443 for https.

       SSL/TLS Protocol
              The protocol parameters negotiated between the client and server. This  will  only  be
              printed if SSL is used.

       Document Path
              The request URI parsed from the command line string.

       Document Length
              This is the size in bytes of the first successfully returned document. If the document
              length changes during testing, the response is considered an error.

       Concurrency Level
              The number of concurrent clients used during the test

       Time taken for tests
              This  is  the time taken from the moment the first socket connection is created to the
              moment the last response is received

       Complete requests
              The number of successful responses received

       Failed requests
              The number of requests that were considered a failure. If the number is  greater  than
              zero,  another  line will be printed showing the number of requests that failed due to
              connecting, reading, incorrect content length, or exceptions.

       Write errors
              The number of errors that failed during write (broken pipe).

       Non-2xx responses
              The number of responses that were not in the 200 series of response codes. If all  re‐
              sponses were 200, this field is not printed.

       Keep-Alive requests
              The number of connections that resulted in Keep-Alive requests

       Total body sent
              If configured to send data as part of the test, this is the total number of bytes sent
              during the tests. This field is omitted if the test did not include a body to send.

       Total transferred
              The  total  number  of  bytes received from the server. This number is essentially the
              number of bytes sent over the wire.

       HTML transferred
              The total number of document bytes received from  the  server.  This  number  excludes
              bytes received in HTTP headers

       Requests per second
              This  is  the  number of requests per second. This value is the result of dividing the
              number of requests by the total time taken

       Time per request
              The average time spent per request. The first value is  calculated  with  the  formula
              concurrency  *  timetaken  * 1000 / done while the second value is calculated with the
              formula timetaken * 1000 / done

       Transfer rate
              The rate of transfer as calculated by the formula totalread / 1024 / timetaken


BUGS
       There are various statically declared buffers of fixed length. Combined with the lazy parsing
       of the command line arguments, the response headers from the server and  other  external  in‐
       puts, this might bite you.


       It  does  not  implement HTTP/1.x fully; only accepts some 'expected' forms of responses. The
       rather heavy use of strstr(3) shows up top in profile, which  might  indicate  a  performance
       problem; i.e., you would measure the ab performance rather than the server's.


Apache HTTP Server                           2018-10-10                                        AB(1)
ab
NAME SYNOPSIS SUMMARY OPTIONS
-A auth-username:password -b windowsize -B local-address -c concurrency -C cookie-name=value -d Do not display the "percentage served within XX [ms] table". (legacy support). -e csv-file -E client-certificate-file -f protocol -g gnuplot-file -h Display usage information. -H custom-header -i Do HEAD requests instead of GET. -k Enable the HTTP KeepAlive feature, i.e., perform multiple requests within one HTTP -l Do not report errors if the length of the responses is not constant. This can be use‐ -m HTTP-method -n requests -p POST-file -P proxy-auth-username:password -q When processing more than 150 requests, ab outputs a progress count on stderr every -r Don't exit on socket receive errors. -s timeout -S Do not display the median and standard deviation values, nor display the warning/error -t timelimit -T content-type -u PUT-file -v verbosity -V Display version number and exit. -w Print out results in HTML tables. Default table is two columns wide, with a white -x -attributes -X proxy[:port] -y -attributes -z -attributes -Z ciphersuite
OUTPUT BUGS

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