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       ab - Apache HTTP server benchmarking tool


       ab  [  -A  auth-username:password  ]  [  -c  concurrency ] [ -C cookie-
       name=value ] [ -d ] [ -e csv-file ] [ -g gnuplot-file ] [  -h  ]  [  -H
       custom-header  ]  [  -i  ] [ -k ] [ -n requests ] [ -p POST-file ] [ -P
       proxy-auth-username:password ] [ -q ] [ -s ] [ -S ] [ -t timelimit ]  [
       -T content-type ] [ -v verbosity] [ -V ] [ -w ] [ -x <table>-attributes
       ] [ -X proxy[:port] ] [ -y <tr>-attributes ]  [  -z  <td>-attributes  ]


       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


       -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 regardless of
              whether  the  server  needs  it   (i.e.,   has   sent   an   401
              authentication needed).

       -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

       -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.

       -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.

       -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.

       -s     When compiled in (ab -h will show you)  use  the  SSL  protected
              https   rather   than   the   http  protocol.  This  feature  is
              experimental 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
              within a fixed total amount of time. Per  default  there  is  no

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

       -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>.


       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.