Ubuntu Manpage: starman - Starman launcher

NAME

       starman - Starman launcher

SYNOPSIS

         starman --listen :5001 --listen /tmp/starman.sock
         starman --workers 32 --port 8080

OPTIONS

-l, --listen
--listen HOST:PORT --listen :PORT --listen UNIX_SOCKET
--listen HOST:PORT:ssl

Specifies the TCP address, ports and UNIX domain sockets to bind to wait for requests. You can repeat
as many times as you want and mix TCP and UNIX domain sockets.

For TCP sockets you can append ":ssl" after the port to specify that connections on that port should
use SSL. Note that the SSL support is experimental and hasn't been widely tested.

Defaults to any IP address and port 5000.

--host
--host 127.0.0.1

Specifies the address to bind.

This option is for a compatibility with plackup and you're recommended to use "--listen" instead.

--port
--port 8080

Specifies the port to bind.

This option is for a compatibility with plackup and you're recommended to use "--listen" instead.

-S, --socket
-S /tmp/starman.sock

Specifies the path to UNIX domain socket to bind.

This option is for a compatibility with plackup and you're recommended to use "--listen" instead.

--workers
Specifies the number of worker pool. Defaults to 5.

Starman by default sets up other spare server configuration based on this workers value, making sure
there are always only "N" worker processes running. So even if there're no idle workers, Starman
won't spawn off spare processes since that's mostly what you want to do by fine tuning the memory
usage etc. in the production environment.

--backlog
Specifies the number of backlog (listen queue size) of listener sockets. Defaults to 1024.

On production systems, setting a very low value can allow failover on frontend proxy (like nginx) to
happen more quickly, if you have multiple Starman clusters.

If you're doing simple benchmarks and getting connection errors, increasing this parameter can help
avoid them. You should also consider increasing "net.core.somaxconn". Note that this is not
recommended for real production system if you have another cluster to failover (see above).

--max-requests
Number of the requests to process per one worker process. Defaults to 1000.

--preload-app
This option lets Starman preload the specified PSGI application in the master parent process before
preforking children. This allows memory savings with copy-on-write memory management. When not set
(default), forked children loads the application in the initialization hook.

Enabling this option can cause bad things happen when resources like sockets or database connections
are opened at load time by the master process and shared by multiple children.

Since Starman 0.2000, this option defaults to false, and you should explicitly set this option to
preload the application in the master process.

Alternatively, you can use -M command line option (plackup's common option) to preload the modules
rather than the <application> itself.

starman -MCatalyst -MDBIx::Class myapp.psgi

will load the modules in the master process for memory savings with CoW, but the actual loading of
"myapp.psgi" is done per children, allowing resource managements such as database connection safer.

If you enable this option, sending "HUP" signal to the master process will not pick up any code
changes you make. See "SIGNALS" for details.

--disable-keepalive
Disable Keep-alive persistent connections. It is an useful workaround if you run Starman behind a
broken frontend proxy that tries to pool connections more than a number of backend workers (i.e.
Apache mpm_prefork + mod_proxy).

--keepalive-timeout
The number of seconds Starman will wait for a subsequent request before closing the connection if
Keep-alive persistent connections are enabled. Setting this to a high value may cause performance
problems in heavily loaded servers. The higher the timeout, the more backend workers will be kept
occupied waiting on connections with idle clients.

Defaults to 1.

--user
To listen on a low-numbered (<1024) port, it will be necessary to start the server as root. Use the
"--user" option to specify a userid or username that the server process should switch to after
binding to the port.

Defaults to the current userid.

--group
Specify the group id or group name that the server should switch to after binding to the port. This
option is usually used with "--user".

Defaults to the current group id.

--pid
Specify the pid file path. Use it with "-D|--daemonize" option, described in "plackup -h".

--error-log
Specify the pathname of a file where the error log should be written. This enables you to still have
access to the errors when using "--daemonize".

--ssl-cert
Specify the path to SSL certificate file.

--ssl-key
Specify the path to SSL key file.

--enable-ssl
Enable SSL on all TCP sockets. This is an experimental feature.

Starman passes through other options given to Plack::Runner, the common backend that plackup uses, so the
most options explained in "plackup -h" such as "--access-log" or "--daemonize" works fine in starman too.

Setting the environment variable "STARMAN_DEBUG" to 1 makes the Starman server running in the debug mode.

SIGNALS

       HUP Sending "HUP" signal to the master process will restart all the workers gracefully (meaning the
           currently running requests will shut down once the request is complete), and by default, the workers
           will pick up the code changes you make by reloading the application.

           If you enable "--preload-app" option, however, the code will be only loaded in the startup process
           and will not pick up the code changes you made. If you want to preload the app and do graceful
           restarts by reloading the code changes, you're recommended to use Server::Starter, configured to send
           "QUIT" signal when superdaemon received "HUP", i.e:

               start_server --interval 5 --port 8080 --signal-on-hup=QUIT -- \
                 starman --preload-app myapp.psgi

           You will then send the HUP signal to "start_server" process to gracefully reload the starman cluster
           (master and workers).

           With Server::Starter 0.12 or later, you should also be able to set "--signal-on-term" to QUIT so that
           you can safely shutdown Starman first and then stop the "start_server" daemon process as well.

       TTIN, TTOU
           Sending "TTIN" signal to the master process will dynamically increase the number of workers, and
           "TTOU" signal will decrease it.

       INT, TERM
           Sending "INT" or "TERM" signal to the master process will kill all the workers immediately and shut
           down the server.

       QUIT
           Sending "QUIT" signal to the master process will gracefully shutdown the workers (meaning the
           currently running requests will shut down once the request is complete).

RELOADING THE APPLICATION

       You're recommended to use signals (see above) to reload the application, and are strongly discouraged to
       use "-r" or "-R" (reloading flag) from plackup. These options will make a separate directory watcher
       process, and makes your life difficult if you want to combine with other process daemon tools such as
       Server::Starter.

DIFFERENCES WITH PLACKUP

       "starman" executable is basically the equivalent of using "plackup" with "Starman" server handler i.e.
       "plackup -s Starman", except that "starman" delay loads the application with the Delayed loader by
       default, which can be disabled with "--preload-app".

       "starman" command also automatically sets the environment ("-E") to the value of deployment.

       You're recommended to use "starman" unless there's a reason to stick to "plackup" for compatibility.

NAME

SYNOPSIS

OPTIONS

SIGNALS

RELOADING THE APPLICATION

DIFFERENCES WITH PLACKUP

SEE ALSO