ab

ab(1)                       General Commands Manual                      ab(1)



NAME
       ab - Apache HTTP server benchmarking tool

SYNOPSIS
       ab [ -k ] [ -e ] [ -q ] [ -S ] [ -i ] [ -s ] [ -n requests ] [ -t
       timelimit ] [ -c concurrency ] [ -p POST file ] [ -A Authenticate
       username:password ] [ -X proxy [ :port ] ] [ -P Proxy Authenticate
       username:password ] [ -H Custom header ] [ -C Cookie name=value ] [ -T
       content-type ] [ -v verbosity ] ] [ -w output HTML ] ] [ -g output
       GNUPLOT ] ] [ -e output CSV ] ] [ -x <table> attributes ] ] [ -y <tr>
       attributes ] ] [ -z <td> attributes ] [http[s]://]hostname[:port]/path

       ab [ -V ] [ -h ]

DESCRIPTION
       ab is a tool for benchmarking the performance of your Apache HyperText
       Transfer Protocol (HTTP) server.  It does this by giving you an
       indication of how many requests per second your Apache installation can
       serve.

OPTIONS
       -k          Enable the HTTP KeepAlive feature; that is, perform
                   multiple requests within one HTTP session. Default is no
                   KeepAlive.

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

       -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
                   deviation apart. And default to the min/avg/max values.
                   (legacy support).

       -s          When compiled in (bb -h will show you) use the SSL
                   protected https rather than the http protocol. This feature
                   is experimental and very rudimentary. You propably do not
                   want to use it.

       -k          Enable the HTTP KeepAlive feature; that is, perform
                   multiple requests within one HTTP session. Default is no
                   KeepAlive.  -i Use an HTTP 'HEAD' instead of the GET
                   method. Cannot be mixed with POST.

       -n requests The number of requests to perform for the benchmarking
                   session.  The default is to perform just one single
                   request, which will not give representative benchmarking
                   results.

       -t timelimit
                   The number of seconds to spend benchmarking. Using this
                   option automatically set the number of requests for the
                   benchmarking session to 50000.  Use this to benchmark the
                   server for a fixed period of time.  By default, there is no
                   timelimit.

       -c concurrency
                   The number of simultaneous requests to perform. The default
                   is to perform one HTTP request at at time, that is, no
                   concurrency.


       -p POST file
                   A file containing data that the program will send to the
                   Apache server in any HTTP POST requests.


       -A Authorization username:password
                   Supply Basic Authentication credentials to the server. The
                   username and password are separated by a single ':', and
                   sent as uuencoded data.  The string is sent regardless of
                   whether the server needs it; that is, has sent a 401
                   Authentication needed.


       -X proxy[:port]
                   Route all requests through the proxy (at optional port).


       -P Proxy-Authorization username:password
                   Supply Basic Authentication credentials to a proxy en-
                   route. The username and password are separated by a single
                   ':', and sent as uuencoded data.  The string is sent
                   regardless of whether the proxy needs it; that is, has sent
                   a 407 Proxy authentication needed.


       -C Cookie name=value
                   Add a 'Cookie:' line to the request. The argument is
                   typically a 'name=value' pair. This option may be repeated.


       -p Header string
                   Append extra headers to the request. The argument is
                   typically in the form of a valid header line, usually a
                   colon separated field value pair, for example, 'Accept-
                   Encoding: zip/zop;8bit'.


       -T content-type
                   The content-type header to use for POST data.


       -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
                   Excell. The labels are on the first line of the file.


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


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


       -v          Sets the verbosity level.  Level 4 and above prints
                   information on headers, level 3 and above prints response
                   codes (for example, 404, 200), and level 2 and above prints
                   warnings and informational messages.


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

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

       -y attributes
                   The string to use as attributes for <tr>.

       -z attributes
                   The string to use as attributes for <td>.

       -V          Display the version number and exit.

       -h          Display usage information.

BUGS
       There are various statically declared buffers of fixed length. Combined
       with inefficient parsing of the command line arguments, the response
       headers from the server, and other external inputs, these buffers might
       overflow.

       Ab does not implement HTTP/1.x fully; instead, it only accepts some
       'expected' forms of responses.

       The rather heavy use of strstr(3) by the program may skew performance
       results, since it uses significant CPU resources.  Make sure that
       performance limits are not hit by ab before your server's limit is
       reached.

       The HTML output is not as complete as the text output.

       Up to version 1.3d ab has propably reported values way to low for most
       measurements; as a single timeout (which is usually in the order of
       seconds) will shift several thousands of milli-second responses by a
       considerable factor. This was further componded by a serious interger
       overrun which would for realistic run's (i.e. those longer than a few
       minutes) produce believable but totally bogus results. Thanks to Sander
       Temme for solving this riddle.


SEE ALSO
       httpd(8)



                                 October 1999                            ab(1)