On Sun, May 14, 2023 at 11:13:46PM -0700, Eric Biggers wrote: > On Mon, May 15, 2023 at 01:38:51AM -0400, Kent Overstreet wrote: > > On Sun, May 14, 2023 at 11:43:25AM -0700, Eric Biggers wrote: > > > I think it would also help if the generated assembly had the handling of the > > > fields interleaved. To achieve that, it might be necessary to interleave the C > > > code. > > > > No, that has negligable effect on performance - as expected, for an out > > of order processor. < 1% improvement. > > > > It doesn't look like this approach is going to work here. Sadly. > > I'd be glad to take a look at the code you actually tried. It would be helpful > if you actually provided it, instead of just this "I tried it, I'm giving up > now" sort of thing. https://evilpiepirate.org/git/bcachefs.git/log/?h=bkey_unpack > I was also hoping you'd take the time to split this out into a userspace > micro-benchmark program that we could quickly try different approaches on. I don't need to, because I already have this: https://evilpiepirate.org/git/ktest.git/tree/tests/bcachefs/perf.ktest > BTW, even if people are okay with dynamic code generation (which seems > unlikely?), you'll still need a C version for architectures that you haven't > implemented the dynamic code generation for. Excuse me? There already is a C version, and we've been discussing it. Your approach wasn't any faster than the existing C version.
