On Mon, Sep 30, 2019 at 09:15:55AM -0700, Linus Torvalds wrote: > On Mon, Sep 30, 2019 at 6:16 AM Theodore Y. Ts'o <ty...@mit.edu> wrote:
> But it _also_ means that if you have a small and excessively stupid > in-order CPU, I can almost guarantee that you will at least have cache > misses likely all the way out to memory. So a CPU-only loop like the > LFSR thing that Thomas reports generates entropy even on its own would > likely generate nothing at all on a simple in-order core - but I do In my experience LFSRs are good at defeating branch predictors, which would make even in-order cores suffer lots of branch misses. And that might be enough, maybe.
