ab(8) ab ab(8)
ab - Apache HTTP server benchmarking tool
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 ] [ -v verbosity] [ -V ] [ -w ] [ -x <table>-attributes ] [ -X proxy[:port] ] [ -y <tr>-attributes ] [ -z <td>-attributes ] [ -Z ciphersuite ] [http[s]://]host- name[:port]/path
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.
-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'. -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 within a fixed total amount of time. Per default there is no timelimit. -T content-type Content-type header to use for POST data, eg. application/x-www- form-urlencoded. Default: text/plain. -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).
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. Apache HTTP Server 2008-10-23 ab(8)
httpd 2.2.11 - Generated Mon Jan 5 20:25:15 CST 2009