Messages in this thread | | | Date | Tue, 04 Nov 2008 12:15:07 -0800 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH RFC/RFB] x86_64, i386: interrupt dispatch changes |
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Jeremy Fitzhardinge wrote: > Ingo Molnar wrote: >> ( another advantage is that the 6 bytes GDT descriptor is more >> compressed and hence uses up less L1/L2 cache footprint than the >> larger (~7 byte) trampolines we have at the moment. ) >> > > Also its D cache rather than I cache, which is generally more > plentiful. However, I think the cost of GDT cache misses on exception > latency is something that we've largely overlooked, and this will make > it a bigger factor (vs cache misses on the actual exception handler code > itself, which should be reduced). >
Besides, a GDT entry is 8 bytes, not 6.
-hpa
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