Parallel Kit Question: ParallelDot is much more slow than Dot
- To: mathgroup at smc.vnet.net
- Subject: [mg40391] Parallel Kit Question: ParallelDot is much more slow than Dot
- From: "Denis Areshkin" <denis at eos.ncsu.edu>
- Date: Thu, 3 Apr 2003 01:45:58 -0500 (EST)
- Organization: NC State University
- Sender: owner-wri-mathgroup at wolfram.com
Dear All,
I appreciate any response on the following problem:
It appears that ParrallelDot function, which is a
part of Parallel Kit, works two orders of magnitude
slower on my two processor machine than Dot. Below
is the commands used to evaluate dot product in pa-
rallel. I am not sure that the command
ExportEnvironment[TestMtrx];
is necessary in that case (though it doesn't do any
harm). It takes 6 seconds to evaluate
Dot[TestMtrx,TestMtrx]
and about half an hour to evaluate
ParallelDot[TestMtrx,TestMtrx]
Needs["Parallel`Parallel`"]
Needs["Parallel`Commands`"]
ProcIDTable = Table[LaunchSlave["localhost",$mathkernel],{2}];
TestMtrx = Table[Random[Real,{-1,1}],{1000},{1000}];
ExportEnvironment[TestMtrx];
TestDot = ParallelDot[TestMtrx,TestMtrx]
I have plenty of RAM (4GB), thus this problem can't
be caused by kernels competing for memory space...
Thank you for your help
--
Denis Areshkin
(919) 513-2424 (office)
(919) 835-1650 (home)