Re: Re: Illusory Multicore Support in 5.2?
- To: mathgroup at smc.vnet.net
- Subject: [mg66070] Re: [mg66041] Re: Illusory Multicore Support in 5.2?
- From: "Pratik Desai <pratikd at wolfram.com>" <Antti.I.Penttila at invalid.helsinki.fi>
- Date: Fri, 28 Apr 2006 06:33:18 -0400 (EDT)
- References: <200604260838.EAA02742@smc.vnet.net> <e2pp8k$su2$1@smc.vnet.net> <200604270836.EAA01610@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Antti Penttilä wrote: > Pratik Desai wrote: > >> Try using SingularValueDecomposition on a sufficiently large matrix >> >> Pratik >> Wolfram Research, Inc. >> Tech Support >> >> > > I have a new dual-core Athlon 64 X2 and WinXP 64-bit edition with > Mathematica 5.2. SingularValueDecomposition with a random 2000x2000 > matrix takes about 41 seconds to complete but the processor load stays > around 50% all the time. It seems that we'll have to start getting some > refund of the price of Mathematica. > > Best regards, > Antti Penttilä > Hello Antti Mathematica 5.2 defaults to using only one thread for linear algebra on Windows. To use multiple threads and take advantage of multiple processors or cores, you will need to set OMP_NUM_THREADS to a value of % NUMBER_OF_PROCESSORS% in your environment. You can do this by going to My Computer and get to the properties template by right clicking and clicking Properties, click the Advanced Tab and then click on Environment Variables. Click on New right below the System Variables list. In the the variable name type in OMP_NUM_THREADS and variable value type in % NUMBER_OF_PROCESSORS% ---------------------------------------- Variable Name : OMP_NUM_THREADS Variable Value: % NUMBER_OF_PROCESSORS% ---------------------------------------- Now you can try your linear algebra operations. Dot on two matrices is the best indicator of your multiprocessing capabilities. If you have have further questions please let me know, or you can e-mail us directly at support at wolfram.com. I apologize for any confusion. Best regards, Pratik -- Pratik Desai Wolfram Research, Inc Technical Support
- References:
- Illusory Multicore Support in 5.2?
- From: "Contrablue" <tetraploidhybrid@hotmail.com>
- Re: Illusory Multicore Support in 5.2?
- From: Antti Penttilä <Antti.I.Penttila@invalid.helsinki.fi>
- Illusory Multicore Support in 5.2?