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NAME ab - Apache HTTP server benchmarking tool SYNOPSIS ab [ -k ] [ -i ] [ -n requests ] [ -t timelimit ] [ -c con- currency ] [ -p POST file ] [ -A Authenticate username:password ] [ -P Proxy Authenticate username:password ] [ -H Custom header ] [ -C Cookie name=value ] [ -T content-type ] [ -v verbosity ] [ -w output HTML ] [ -x <table> attributes ] [ -X proxy[:port] ] [ -y <tr> attributes ] [ -z <td> attributes ] [http://]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, per- form 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 bench- marking 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 a 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. The contents of the file should look like
name=value&something=other, with special characters URL encoded. -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 Authen- tication needed. -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 argu- ment is typically a 'name=value' pair. This option may be repeated. -H Header string Append extra headers to the request. The argu- ment 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. -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 infor- mational messages. -w Print out results in HTML tables. The default table is two columns wide, with a white back- ground. -x attributes The string to use as attributes for <table>. Attributes are inserted <table here > -X proxy:port Use the specified proxy server, running on the specified port. -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. SEE ALSO httpd(8)