Wireshark-dev: Re: [Wireshark-dev] Optimization
From: Mike Duigou <[email protected]>
Date: Fri, 26 Oct 2007 08:51:09 -0700
Using various machine settings as a way to improve performance is a common topic on Linux kernel discussion lists. The summary though from what I've read is that for almost all cases the various tunings between i386 and i686 SSE rarely make any appreciable difference at all. A few specific cases for atomic operations and 64-bit math do exist but they aren't heavily used enough to matter.
The Mozilla team came to a similar conclusion, that architecture 
optimization delivered nothing except incompatibility. They have 
actually switched to using code size optimization for most of the source 
base (resulting in a 3-5% reduction in executable size).  They showed 
that having more code in the cache beat a speed optimized version in 
their standard test suites. Speed optimizations are used only for a few 
key routines. In some cases they recoded these routines so that they 
generated the almost the same code with or without optimization so as to 
get performance benefits on all supported platforms.
YMMV,

Mike

Anders Broman wrote:
Hi,
Would we get any performance gain by switching to /MACHINE:I686?
As we are no longer suporting older Windows versions there is no need to suport I386 I suppose…
Regards
Anders