VIP23 (VSL refactoring) design sketch

Nils Goroll nils.goroll at
Wed Apr 10 14:24:13 UTC 2019

On 10/04/2019 16:07, Poul-Henning Kamp wrote:
> If each VSL record invokes its own C-function, we eat up a LOT of L1+L2
> cache bandwidth. If they all call the same function, we do not.

OK, understood.

I wonder though if all things considered (format string parsing, definition
lookup, varargs processing) this pays off. I got no data on this, but one
counter-argument might be that, for custom functions, one would expect no/very
few conditionals, so we would likely see no/very few pipeline stalls .



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