On Tue, Jul 3, 2012 at 5:56 PM, Akio Yamamoto <yamam...@tkl.iis.u-tokyo.ac.jp> wrote:
> Yes, as Richard pointed out, I just wanted to know the numbers for input > to Amdahl's law, if you have already something, to figure out the maximum > expected speedup using multiple processors/cores. > > As for improvements of em_reg, I'll try to split each transform as well as > parallelize the energy evaluation. Parallelising the energy evaluation is the lowest hanging fruit, and is what happens in the 'slow' GPU version. But for highest performance, I would convert the nested transform loops into a single one, and farm those out between OpenMP threads (I wouldn't bother trying nested parallelism of the energy evaluation, although you might want to do some SSE tinkering). That is effectively what happens in the 'fast' GPU version - you can use the same basic structure. But be aware that the slightly different transforms which result can cause you to converge to a different solution. HTH, Richard _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Partners Compliance HelpLine at http://www.partners.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.