SIEGE(1) Siege v2.70 SIEGE(1)
July-19-2010
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
configuration 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.
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-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
combinations: -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
SIEGE_HOME/var/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
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SIEGE(1) Siege v2.70 SIEGE(1)
July-19-2010
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 SIEGE_HOME/etc/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
protocol, the minimum URL requirement is this: https://shemp. That
URL specification will lay siege to
https://shemp.yourdomain.net/index.html
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July-19-2010
URLS FILE
To hit multiple URLs, place them in a single file. The default URLs
file is $SIEGE_HOME/etc/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
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SIEGE(1) Siege v2.70 SIEGE(1)
July-19-2010
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
transactions. 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 follows 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
completes 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.
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July-19-2010
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
MERCHANTABILITY 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)
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