SIEGE(1) General Commands Manual SIEGE(1)
NAME
siege - An HTTP/HTTPS stress tester
INTRODUCTION
Siege is a multi-threaded http load testing and benchmarking utility. It was designed to let web developers measure the performance of
their code under duress. It allows one to hit a web server with a configurable number of concurrent simulated users. Those users place
the webserver "under siege." Performance measures include elapsed time, total data transferred, server response time, its transaction
rate, its throughput, its concurrency and the number of times it returned OK. These measures are quantified and reported at the end of
each run. Their meaning and significance is discussed below. Siege has essentially three modes of operation: regression (when invoked by
bombardment), internet simulation and brute force.
INVOCATION
The format for invoking siege is: siege [options]
siege [options] [url]
siege -g [url]
Siege supports the following command line options:
-V, --version
VERSION, prints the version number
-h, --help
HELP, prints the help section which includes a summary of all the command line options.
-C, --config
CONFIGURATION, prints the current configuration in the $HOME/.siegerc file. Edit that file to set flag values for EVERY siege run,
a feature which eases runtime invocation. You set an alternative resource file with the SIEGERC environment variable: export
SIEGERC=/home/jeff/haha
-v, --verbose
VERBOSE, prints the HTTP return status and the GET request to the screen. Useful when reading a series of URLs from a con-
figuration file. This flag allows you to witness the progress of the test.
-g, --get
GET, pull down HTTP headers and display the transaction. Great for web server configuration debugging. Requires a URL be passed to
siege on the command line.
-c NUM, --concurrent=NUM
CONCURRENT, allows you to set the concurrent number of simulated users to num. The number of simulated users is limited to the
resources on the computer running siege.
-i, --internet
INTERNET, generates user simulation by randomly hitting the URLs read from the urls.txt file. This option is viable only with the
urls.txt file.
-d NUM, --delay=NUM
DELAY, each siege simulated users sleeps for a random interval in seconds between 0 and NUM.
-b, --benchmark
BENCHMARK, runs the test with NO DELAY for throughput benchmarking. By default each simulated user is invoked with at least a one
second delay. This option removes that delay. It is not recommended that you use this option while load testing.
-r NUM, --reps=NUM, --reps=once
REPS, allows you to run the siege for NUM repetitions. If --reps=once, then siege will run through the urls.txt file one time and
stop when it reaches the end. NOTE: -t/--time takes precedent over -r/--reps. If you want to use this option, make sure time = x is
commented out in your $HOME/.siegerc file.
-t NUMm, --time=NUMm
TIME, allows you to run the test for a selected period of time. The format is "NUMm", where NUM is a time unit and the "m" modifier
is either S, M, or H for seconds, minutes and hours. To run siege for an hour, you could select any one of the following combina-
tions: -t3600S, -t60M, -t1H. The modifier is not case sensitive, but it does require no space between the number and itself.
-l [FILE], --log[=FILE]
LOG transaction stats to FILE. The argument is optional. If FILE is not specified, then siege logs the transaction to
/var/log/siege.log. If siege is installed in /usr/local, then the default siege.log is /usr/local/var/siege.log. This option logs
the final statistics reported when siege successfully completes its test. You can edit $HOME/.siegerc to change the location of the
siege.log file.
-m MESSAGE, --mark=MESSAGE
MARK, mark the log file with a separator. This option will allow you to separate your log file entries with header information.
This is especially useful when testing two different servers. It is not necessary to use both the -m option and the -l option. -m
assumes -l so it marks and logs the transaction. If the MESSAGE has spaces in it, make sure that you put it in quotes.
-H HEADER, --header=HEADER
HEADER, this option allows you to add additional header information.
-R SIEGERC, --rc=SIEGERC
RC, sets the siegerc file for the run. This option overrides the environment variable SIEGERC and the default resource file,
$HOME/.siegerc
-f FILE, --file=FILE
FILE, the default URL file is /etc/siege/urls.txt. To select a different URL file, use this option, i.e., siege -f myurls.txt
-A "User Agent", --user-agent="User Agent"
AGENT, use this option to set the User-Agent in the request.
URL FORMAT
Siege understands the following URL formats:
(brackets indicate the directive is optional)
[protocol://] host.domain.xxx [:port] [/path/file]
host.domain.xxx/file POST field=value&field2=value2
Or you can POST the contents of a file using the line input operator, the "<" character:
host/file POST </home/jeff/haha.txt
The first example above is an implicit GET, the next two are obviously POSTs. You can pass parameters using GET much like you would in a
web browser:
www.haha.com/form.jsp?first=homer&last=simpson
If you invoke the URL as a command line argument, you should probably place it in quotes. Currently, it supports two protocols, http and
https. If a protocol is not specified, then siege assumes http. The minimum URL requirement is this: servername. That's it. So if
you're in the same domain as a server named shemp and shemp is in your host file or it is in DNS, then: "siege shemp" will stress
http://shemp.yourdomain.net/index.html (assuming that "index.html" is the server specified index). To stress the same page using https pro-
tocol, the minimum URL requirement is this: https://shemp. That URL specification will lay siege to https://shemp.yourdo-
main.net/index.html
URLS FILE
To hit multiple URLs, place them in a single file. The default URLs file is /etc/siege/urls.txt. [You may change that file with the -f
option, see above.] In that file list the URLs one per line:
# place all your comments behind hashes
http://homer.whoohoo.com/index.html
http://homer.whoohoo.com/howto.jsp
http://go.whoohoo.com/cgi-bin/q.cgi?scope=a
http://go.whoohoo.com/cgi-bin/q.cgi POST scope=a
http://homer.whoohoo.com/my.jsp POST a=1&b=2
# POST the contents of a file...
www.haha.com/aha.jsp POST </home/jeff/my.txt
www.haha.com/parser.jsp POST <./my.txt
When invoked without a URL on the command line, siege looks for URLs in a file. Normally, it reads them all into memory and runs through
them sequentially. If you specify internet mode [-i], then it randomly selects URLs to hit.
You may set and reference variables in URLs file. It is necessary to set them PRIOR to referencing them. The syntax for defining variables
is NAME = VALUE with a single assignment on a single line. If you define several variables in the file, you must place each assignment on a
single line. To use the value of the variable, you must reference it inside $() or ${}, i.e., $(NAME). If you reference a variable that
doesn't exist, siege will evaluate it to the empty string "".
# Example using variable assignment
# in the urls.txt file.
HOST = homer.whoohoo.com
http://${HOST}/index.html
http://${HOST}/howto.jsp
PERFORMANCE STATISTICS
Performance measures include elapsed time of the test, the amount of data transferred ( including headers ), the response time of the
server, its transaction rate, its throughput, its concurrency and the number of times it returned OK. These measures are quantified and
reported at the end of each run. The reporting format is modeled after Lincoln Stein's torture.pl script:
** Siege 2.60
** Preparing 100 concurrent users for battle.
The server is now under siege...done
Transactions: 339 hits
Availability: 93.39 %
Elapsed time: 67.47 secs
Data transferred: 4273708 bytes
Response time: 8.25 secs
Transaction rate: 5.02 trans/sec
Throughput: 63342.34 bytes/sec
Concurrency: 41.47
Successful transactions: 337
Failed transactions: 26
Longest transaction: 17.77 secs
Shortest transaction: 0.37 secs
Transactions
The number of server hits. In the example, 25 simulated users [ -c25 ] each hit the server 10 times [ -r10 ], a total of 250 trans-
actions. It is possible for the number of transactions to exceed the number of hits that were scheduled. Siege counts every server
hit a transaction, which means redirections and authentication challenges count as two hits, not one. With this regard, siege fol-
lows the HTTP specification and it mimics browser behavior.
Availability
This is the percentage of socket connections successfully handled by the server. It is the result of socket failures (including
timeouts) divided by the sum of all connection attempts. This number does not include 400 and 500 level server errors which are
recorded in "Failed transactions" described below.
Elapsed time
The duration of the entire siege test. This is measured from the time the user invokes siege until the last simulated user com-
pletes its transactions. Shown above, the test took 14.67 seconds to complete.
Data transferred
The sum of data transferred to every siege simulated user. It includes the header information as well as content. Because it
includes header information, the number reported by siege will be larger then the number reported by the server. In internet mode,
which hits random URLs in a configuration file, this number is expected to vary from run to run.
Response time
The average time it took to respond to each simulated user's requests.
Transaction rate
The average number of transactions the server was able to handle per second, in a nutshell: transactions divided by elapsed time.
Throughput
The average number of bytes transferred every second from the server to all the simulated users.
Concurrency
The average number of simultaneous connections, a number which rises as server performance decreases.
Successful transactions
The number of times the server responded with a return code < 400.
Failed transactions
The number of times the server responded with a return code >= 400 plus the sum of all failed socket transactions which includes
socket timeouts.
Longest transaction
The greatest amount of time that any single transaction took, out of all transactions.
Shortest transaction
The smallest amount of time that any single transaction took, out of all transactions.
AUTHOR
Jeffrey Fulmer, et al. <jeff@joedog.org>
BUGS
Report bugs to jeff@joedog.org. Give a detailed description of the problem and report the version of siege that you are using.
COPYRIGHT
Copyright (C) 2000 2001 2004 Jeffrey Fulmer, et al.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MER-
CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation,
Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
AVAILABILITY
The most recent released version of siege is available by anonymous FTP from ftp.joedog.org in the directory pub/siege.
SEE ALSO
siege.config(1) urls_txt(5) layingsiege(7)
Siege v2.70 April-17-2012 SIEGE(1)