3 ms·
All the various bits that get tacked on for doing prefetch and branch prediction all are fairly large too, given the amount of random caching, which often is wh
by buildbot 1y ago
All the various bits that get tacked on for doing prefetch and branch prediction all are fairly large too, given the amount of random caching, which often is what people account for when measuring decode power usage I think. That’s going to be the case in any arch besides something like a DSP without any kind of dynamic dispatch.
- jeffbee 1y agoI think it's safe to say that a modern x86 branch predictor with its BTBs is significantly larger than the decode block.
- adgjlsfhk1 1y agoSure, but branch prediction is (as far as we know) a necessary evil. Decode complexity simply isn't.
- buildbot 1y agoRight, but decode compexity doesn't matter because of the giant BTB and such. At least that's what I understand.
- throwaway31131 1y agoFor the cores working hardest to achieve the absolute lowest cpi running user code, this is true. But these days the computers have computers in them to manage the system. And these kinds of statements aren’t necessarily true for these “inner cores” that aren’t user accessible. “ RTKit: Apple's proprietary real-time operating system. Most of the accelerators (AGX, ANE, AOP, DCP, AVE, PMP) run RTKit on an internal processor. The string "RTKSTACKRTKSTACK" is characteristic of a firmware containing RTKit.” https://asahilinux.org/docs/project/glossary/#r https://asahilinux.org/docs/project/glossary/#r