3 ms·
The crazy thing to me is that the overhead of all this bookkeeping and extra hardware complexity adds up to less than the performance improvement.
by afandian 4y ago
The crazy thing to me is that the overhead of all this bookkeeping and extra hardware complexity adds up to less than the performance improvement.
- tambourine_man 4y agoWhere did you get that from?
- afandian 4y agoJust implicature. I assume that there was a net benefit to adding all of these features.
- tambourine_man 4y agoI don’t get what your are saying. OoO and speculative execution can increase speed dramatically. It’s a lot more complex and potentially dangerous, but all high performance cores do this so it’s obviously worth it.
- afandian 4y agoWhat PoignardAzur said. The machinery to instrument and calculate probabilities on branches. Maintaining state enough that speculatively executed branches can be rolled back. That sounds non-trivial and I imagine it would take a lot of real estate, energy, etc.
- tambourine_man 4y agoYeah, I got it on a third read :) Agreed.
- PoignardAzur 4y agoTo be clear, I think GP is saying "that stuff manages to be cheap enough that the performance improvements more than make up for the overhead".
- tambourine_man 4y agoAh, makes sense now. Thanks.