lsst.ctrl.pool.pool.Comm Class Reference

Inheritance diagram for lsst.ctrl.pool.pool.Comm:

Public Member Functions
def	__new__ (cls, comm=mpi.COMM_WORLD, recvSleep=0.1, barrierSleep=0.1)
	Construct an MPI.Comm wrapper. More...
def	recv (self, obj=None, source=0, tag=0, status=None)
def	send (self, obj=None, args, kwargs)
def	Barrier (self, tag=0)
def	broadcast (self, value, root=0)
def	scatter (self, dataList, root=0, tag=0)
def	Free (self)

Detailed Description

Wrapper to mpi4py's MPI.Intracomm class to avoid busy-waiting.

As suggested by Lisandro Dalcin at:
* http://code.google.com/p/mpi4py/issues/detail?id=4 and
* https://groups.google.com/forum/?fromgroups=#!topic/mpi4py/nArVuMXyyZI

Definition at line 243 of file pool.py.

Member Function Documentation

__new__()

def lsst.ctrl.pool.pool.Comm.__new__	(		cls,
			comm = mpi.COMM_WORLD,
			recvSleep = 0.1,
			barrierSleep = 0.1
	)

Construct an MPI.Comm wrapper.

Parameters

cls	Class
comm	MPI.Intracomm to wrap a duplicate of
recvSleep	Sleep time (seconds) for recv()
barrierSleep	Sleep time (seconds) for Barrier()

Definition at line 251 of file pool.py.

Barrier()

def lsst.ctrl.pool.pool.Comm.Barrier	(		self,
			tag = 0
	)

Version of comm.Barrier() that doesn't busy-wait

A duplicate communicator is used so as not to interfere with the user's own communications.

Definition at line 281 of file pool.py.

broadcast()

def lsst.ctrl.pool.pool.Comm.broadcast	(		self,
			value,
			root = 0
	)

Definition at line 302 of file pool.py.

Free()

def lsst.ctrl.pool.pool.Comm.Free

(

self

)

Definition at line 330 of file pool.py.

recv()

def lsst.ctrl.pool.pool.Comm.recv	(		self,
			obj = None,
			source = 0,
			tag = 0,
			status = None
	)

Version of comm.recv() that doesn't busy-wait

Definition at line 265 of file pool.py.

scatter()

def lsst.ctrl.pool.pool.Comm.scatter	(		self,
			dataList,
			root = 0,
			tag = 0
	)

Scatter data across the nodes

The default version apparently pickles the entire 'dataList',
which can cause errors if the pickle size grows over 2^31 bytes
due to fundamental problems with pickle in python 2. Instead,
we send the data to each slave node in turn; this reduces the
pickle size.

@param dataList  List of data to distribute; one per node
    (including root)
@param root  Index of root node
@param tag  Message tag (integer)
@return  Data for this node

Definition at line 306 of file pool.py.

send()

def lsst.ctrl.pool.pool.Comm.send	(		self,
			obj = None,
			args,
			kwargs
	)

Definition at line 272 of file pool.py.

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The documentation for this class was generated from the following file:

• python/lsst/ctrl/pool/pool.py