Re: Re: Multicore Calculations
- To: mathgroup at smc.vnet.net
- Subject: [mg60862] Re: [mg60809] Re: [mg60769] Multicore Calculations
- From: Manuel Schmidt <Manuel.Schmidt at physik.uni-wuerzburg.de>
- Date: Fri, 30 Sep 2005 06:38:00 -0400 (EDT)
- References: <200509280541.BAA08344@smc.vnet.net> <200509290941.FAA01101@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi, this are the informations about my system: Dual Opteron 2G RAM SuSE Prof. 9.3 Mathematica 5.2 The threads do not show up independently on this system (it is a cip-pool). On my local computer, I have only one processor (Athlon64) with Gentoo (I know, it is not supported) running and there the kernel uses 4 processes. Can one set from outside (as user or installer) how many Threads a kernel uses? Thanks, Manuel On Thu, 2005-09-29 at 05:41 -0400, Jeff Bryant wrote: > The results you get depend on a couple of factors. I'll provide a > couple comments and perhaps other, more qualified people can respond > directly if necessary for additional details. > > What platform (CPU and OS) are you running on? That will determine if > a) we support multiple processors/cores > and > b) if top shows threads independently of their parent process. > > Also, vector-vector (BLAS level 1) and matrix-vector operations (BLAS > level 2) don't parallelize terribly well, so there will be little > benefit to multiple processors for those types of operations, anyway. > > -Jeff > > Manuel Schmidt wrote: > > > Hi all, > > > > i'm wondering, how one can convince the MathKernel to do a numerical > > linear algebra calculation on two processors at the same time in 5.2. > > > > Am I right, that this should be computed on two processors (if > > available): > > > > vec1 = Table[Random[], {i, 5000000}]; > > vec2 = Table[Random[], {i, 5000000}]; > > > > While[True,Dot[vec1, vec2]] > > > > or a big matrix and a vector > > > > matrix.vector; > > > > Anyways, I see in top only one kernel running. There is only one thread. > > Are there different binaries for the multicore and the singlecore > > version? > > > > Thanks, > > > > Manuel > > > >
- References:
- Multicore Calculations
- From: Manuel Schmidt <Manuel.Schmidt@physik.uni-wuerzburg.de>
- Re: Multicore Calculations
- From: Jeff Bryant <jeffb@wolfram.com>
- Multicore Calculations