Date: Sun, 21 Apr 2013 14:26:02 +0200 From: magnum <john.magnum@...hmail.com> To: john-dev@...ts.openwall.com Subject: Re: minor raw-sha1-ng pull request On 21 Apr, 2013, at 1:27 , Solar Designer <solar@...nwall.com> wrote: > Tavis, magnum - > > On Fri, Apr 19, 2013 at 06:25:50PM -0700, Tavis Ormandy wrote: >> Thanks for the explanation Magnum, I get similar results! I can restructure >> cmp_all so it's also omp safe, I sent you a pull request for that. It get's >> anoter 2000K c/s on my machine. > > Thanks! > > The attached patch replaces the heavy "#pragma omp atomic" with much > lighter OpenMP reduction for the bitwise OR. I've checked the OpenMP 2.5 > spec (from 2005) - bitwise OR was already supported in the reduction > clause, so I think we're good in terms of portability. This is committed. Unstable branch still has the non-OMP version. Should we merge these changes to it? > Also, I get better speeds at high thread counts when OMP_SCALE is much > larger - not the current 32, but 1024 or even 10240. With 32, there's a > performance regression when going from 4 to 8 threads on FX-8120. With > 1024, there's slight speedup. With 10240, it's roughly 50M vs. 60M c/s > for 4 vs. 8 threads. On Intel I get an overall regression at 10240 (and it makes --test=1 run for 8 seconds). I think I'll bump it to 1024 for now. magnum
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.