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RE: Ubuntu Precise PPA
by Mike Mestnik on Thursday May 10th 2012, 16:17
I wouldn't use x86_64, the way some wine devs wouldn't use PulseAudio.
Generally the issue is all the converting of data, specifically floats but signed integers as well, that adds extra computation time. Also note that the opcodes for emulating the x86_32 instruction set while running in LongMode are both incomplete and buggy. There may also be hidden penalties for entering and exiting LongMode which can add to the cost of a context switch...
Generally it's just a rant against any one ever using x86_64 and all the problems I believe it adds, not that you should in any way let my opinion alter the way you do things.