ab(1)							      General Commands Manual							     ab(1)

NAME

       ab - Apache HTTP server benchmarking tool

SYNOPSIS

       ab  [ -k ] [ -e ] [ -q ] [ -S ] [ -i ] [ + .B -s ] [ -n requests ] [ -t timelimit ] [ -c concurrency ] [ -p POST file ] [ -A Authentication
       username:password ] [ -P Proxy Authentication username:password ] [ -H Custom header ] [ -C Cookie name=value ] [ -T content-type  ]  [	-X
       proxy [ :port ] ] [ -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 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 serv-
       ing.

OPTIONS

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

       -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 results.

       -t timelimit
		   Maximum  number  of seconds to spend for benchmarking. This implies -d Do not display the "percentage served within XX [ms] ta-
		   ble". (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.   a	-n
		   50000 internally. Use this to benchmark the server within a fixed total amount of time.  Per default there is no timelimit.

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

       -p POST file
		   File containing data to POST.

       -A Authentication username:password
		   Supply  BASIC Authentication credentials to the server. The username and password are separated by a single ':' and sent on the
		   wire uuencoded.  The string is sent regardless of whether the server needs it; (i.e., has sent an 401 authentication needed).

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

       -P Proxy-Authentication 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 uuencoded.  The string is sent regardless of whether the proxy needs it; (i.e., has sent an 407 proxy authentica-
		   tion needed).

       -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.

       -p Header string
		   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').

       -T content-type
		   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	   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.

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

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

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

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

       -V	   Display version number and exit.

       -h	   Display usage information.

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 inputs, 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.

SEE ALSO

       httpd(8)

       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 <sander@covalent.net> for solving this riddle.

								    March 2000								     ab(1)