


AB(8)                           ab                          AB(8)


NAME
       ab - Apache HTTP server benchmarking tool


SYNOPSIS
       ab [ -A auth-username:password ] [ -b windowsize ] [ -c concurrency ] [
       -C cookie-name=value ] [ -d ] [ -e csv-file ] [ -f protocol ] [ -g gnu-
       plot-file ] [ -h ] [ -H custom-header ] [ -i ] [ -k ] [ -n requests ] [
       -p POST-file ] [ -P proxy-auth-username:password ] [ -q ] [ -r ] [ -s ]
       [  -S  ] [ -t timelimit ] [ -T content-type ] [ -u PUT-file ] [ -v ver-
       bosity] [ -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  especially  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 user-
              name  and  password  are separated by a single : and sent on the
              wire base64 encoded. The string is sent  regardless  of  whether
              the  server  needs  it  (i.e.,  has  sent  an 401 authentication
              needed).

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

       -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'.




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AB(8)                           ab                          AB(8)


       -f protocol
              Specify SSL/TLS protocol (SSL2, SSL3, TLS1, or ALL).

       -g gnuplot-file
              Write  all  measured values out as a 'gnuplot' or TSV (Tab sepa-
              rate values) file. This file can easily be imported  into  pack-
              ages  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.

       -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.

       -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  authen-
              tication 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     When  compiled  in  (ab  -h will show you) use the SSL protected
              https rather than the http protocol. This feature is  experimen-
              tal and very rudimentary. You probably do not want to use it.

       -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).

       -t timelimit
              Maximum number  of  seconds  to  spend  for  benchmarking.  This
              implies  a -n 50000 internally. Use this to benchmark the server



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AB(8)                           ab                          AB(8)


              within a fixed total amount of time. Per  default  there  is  no
              timelimit.

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


BUGS
       There are various statically declared buffers of fixed length. Combined
       with the lazy parsing of the command line arguments, the response head-
       ers 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.










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