Thread: Optimizations for Xeon E5320?
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Old 29th October 2008
richardpl richardpl is offline
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Originally Posted by phoenix View Post
This page shows all the different copy functions configured when I586_CPU is enabled. There are no entries for I686_CPU in there, which tells me that all the optimisations are enabled for I585_CPU and not for I686_CPU.
But it is enabled only if cpu actually have npx (DEV_NPX defined), 686 CPU do not have that coprocessor. (ony 486DX CPU, and systems with 387 or 487SX coprocessors)
This npx(4) man page may shed more light.
I think if it is possible on some of such CPUs to build kernel without I586_CPU and than npx routines would be emulated - slower.
Last edited by richardpl; 29th October 2008 at 10:42 AM.
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