tornado::process Namespace Reference

Classes
class	Subprocess
Functions
def	_pipe_cloexec
def	_reseed_random
def	cpu_count
def	fork_processes
def	task_id
Variables
	_task_id = None
	long = int
	multiprocessing = None

---

Function Documentation

def tornado.process._pipe_cloexec

(

)

[private]

Definition at line 81 of file process.py.

def tornado.process._reseed_random

(

)

[private]

Definition at line 67 of file process.py.

def tornado.process.cpu_count

(

)

Returns the number of processors on this machine.

Definition at line 51 of file process.py.

def tornado.process.fork_processes	(		num_processes,
			max_restarts = 100
	)

Starts multiple worker processes.

If ``num_processes`` is None or <= 0, we detect the number of cores
available on this machine and fork that number of child
processes. If ``num_processes`` is given and > 0, we fork that
specific number of sub-processes.

Since we use processes and not threads, there is no shared memory
between any server code.

Note that multiple processes are not compatible with the autoreload
module (or the ``autoreload=True`` option to `tornado.web.Application`
which defaults to True when ``debug=True``).
When using multiple processes, no IOLoops can be created or
referenced until after the call to ``fork_processes``.

In each child process, ``fork_processes`` returns its *task id*, a
number between 0 and ``num_processes``.  Processes that exit
abnormally (due to a signal or non-zero exit status) are restarted
with the same id (up to ``max_restarts`` times).  In the parent
process, ``fork_processes`` returns None if all child processes
have exited normally, but will otherwise only exit by throwing an
exception.

Definition at line 91 of file process.py.

def tornado.process.task_id

(

)

Returns the current task id, if any.

Returns None if this process was not created by `fork_processes`.

Definition at line 175 of file process.py.

---

Variable Documentation

tornado::process::_task_id = None

Definition at line 88 of file process.py.

tornado::process::long = int

Definition at line 48 of file process.py.

tornado::process::multiprocessing = None

Definition at line 43 of file process.py.