Date: Thu, 8 Sep 2016 12:03:16 +0800 From: Lei Zhang <zhanglei.april@...il.com> To: john-dev@...ts.openwall.com Subject: Re: Intel KNL test machine 2016-09-08 5:14 GMT+08:00 Lukas Odzioba <lukas.odzioba@...il.com>: > 2016-09-07 15:25 GMT+02:00 Solar Designer <solar@...nwall.com>: >> Yes, thanks. Lukas already ran some benchmarks on a similar device, but >> I think he never published those, in part because the descrypt ones were >> for AVX2 rather than AVX-512. > > I think I can find some spare time this weekend to try to fix code, > rerun my tests > and post results, unless Lei wants to do this - which I don't mind :) > > Have in mind that AVX512 there is a different set of instructions from > those on KNC, > so it's better to use some recent compiler. Also Linux kernel must > support avx512, > which you can check via $ cat /proc/cpuinfo | grep -i avx512 > There should be avx512f, avx512pf, avx512cd, avx512er extensions. The memory model also changed. In KNC native mode, all memory usage happens in the co-processor's 8GB high-bandwidth memory (I forgot the exact name...). But KNL is a host CPU; it supports normal DDR and in the meantime also has its own high-bandwidth memory, which is called MCDRAM . DDR is the default; special functions are needed to utilize MCDRAM. I don't know how much impact memory throughput has on John's performance. Perhaps John needs to explicitly support KNL's memory model to fully extract performance from it. Lei  http://www.hotchips.org/wp-content/uploads/hc_archives/hc27/HC27.25-Tuesday-Epub/HC27.25.70-Processors-Epub/HC27.25.710-Knights-Landing-Sodani-Intel.pdf
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.