NAME¶
gunicorn_paster - Event-based HTTP/WSGI server, Paste application entry-point
SYNOPSIS¶
gunicorn_paster [OPTIONS] [SETTINGS_PATH]
OPTIONS¶
- -c CONFIG, --config=CONFIG
- Config file. [none]
- -b BIND, --bind=BIND
- Address to listen on. Ex. 127.0.0.1:8000 or unix:/tmp/gunicorn.sock
- -w WORKERS, --workers=WORKERS
- Number of workers to spawn. [1]
- -a ARBITER, --arbiter=ARBITER
- gunicorn arbiter entry point or module [egg:gunicorn#main]
- -p PIDFILE, --pid=PIDFILE
- Set the background PID FILE
- -D, --daemon
- Run daemonized in the background.
- -m UMASK, --umask=UMASK
- Define umask of daemon process
- -u USER, --user=USER
- Change worker user
- -g GROUP, --group=GROUP
- Change worker group
- -n PROC_NAME, --name=PROC_NAME
- Process name
- --log-level=LOGLEVEL
- Log level below which to silence messages. [info]
- --log-file=LOGFILE
- Log to a file. - equals stdout. [-]
- d, --debug
- Debug mode. only 1 worker.
- --version
- Show program's version number and exit
- -h, --help
- show this help message and exit
DESCRIPTION¶
Green Unicorn (gunicorn) is an HTTP/WSGI server designed to serve fast clients
or sleepy applications. That is to say; behind a buffering front-end server
such as nginx or lighttpd.
* Optional support for Eventlet and Gevent to provide asynchronous
long-polling ("Comet") connections.
* Process management: Gunicorn reaps and restarts workers that die.
* Easy integration with Django and Paster compatible applications (Pylons,
TurboGears 2, etc.
* Load balancing via pre-fork and a shared socket
* Graceful worker process restarts
* Upgrading without losing connections
* Decode chunked transfers on-the-fly, allowing upload progress notifications
or stream-based protocols over HTTP
TUNING¶
KERNEL PARAMETERS¶
There are various kernel parameters that you might want to tune in order to deal
with a large number of simultaneous connections. Generally these should only
affect sites with a large number of concurrent requests and apply to any sort
of network server you may be running. They're listed here for ease of
reference.
The commands listed are tested under Mac OS X 10.6. Your flavor of Unix may use
slightly different flags. Always reference the appropriate man pages if
uncertain.
INCREASING THE FILE DESCRIPTOR LIMIT¶
One of the first settings that usually needs to be bumped is the maximum number
of open file descriptors for a given process. For the confused out there,
remember that Unices treat sockets as files.
$ sudo ulimit -n 1024
INCREASING THE LISTEN QUEUE SIZE¶
Listening sockets have an associated queue of incoming connections that are
waiting to be accepted. If you happen to have a stampede of clients that fill
up this queue new connections will eventually start getting dropped.
$ sudo sysctl -w kern.ipc.somaxconn="1024"
WIDENING THE EPHEMERAL PORT RANGE¶
After a socket is closed it eventually enters the TIME_WAIT state. This can
become an issue after a prolonged burst of client activity. Eventually the
ephemeral port range is used up which can cause new connections to stall while
they wait for a valid port.
This setting is generally only required on machines that are being used to test
a network server.
SEE ALSO¶
gunicorn(1)