|
Message-ID: <CAKGDhHUq6d33nGTFT65MdrzMMYodoZyHRHeZmmvTbTRRFJfmHQ@mail.gmail.com> Date: Sun, 16 Aug 2015 22:27:27 +0200 From: Agnieszka Bielec <bielecagnieszka8@...il.com> To: john-dev@...ts.openwall.com Subject: Re: PHC: Argon2 on GPU 2015-08-16 16:09 GMT+02:00 Solar Designer <solar@...nwall.com>: > On Sun, Aug 16, 2015 at 03:03:56PM +0200, Agnieszka Bielec wrote: >> 2015-08-16 14:48 GMT+02:00 Solar Designer <solar@...nwall.com>: >> > On Sun, Aug 16, 2015 at 02:01:38PM +0200, Agnieszka Bielec wrote: >> >> prev_block[i] = ((__global ulong2*)memory)[bi+i]; >> >> } >> >> >> >> see anyone some logic here or is this just a bug on AMD? >> > >> > Why do you call this a bug? It isn't necessarily a bug when performance >> > of code changes when you change the source code. >> > >> > Anyway, it looks like in the second code version you rely on address >> > scaling by 16, and this is probably not available in the architecture >> > (usually available is scaling by up to 8), so requires extra >> > instructions (explicit left shifts). >> >> where do you see address scaling? > > bi+i is used to index an array if 16-byte elements, so it needs to be > multiplied by 16 each time (unless the compiler manages to optimize > this, perhaps much like you had done manually in the first version). if something is not supported why I have on my laptop the opposite of this slowdown on AMD? although only slightly, when I modify the newest code as in my previous e-mail I have the same speed for tests when gws is set and when gws is not set none@...e ~/Desktop/r/run $ ./john --test --format=argon2d-opencl Benchmarking: argon2d-opencl [Blake2 OpenCL]... memory per hash : 1.46 MB Device 0: GeForce GTX 960M using different password for benchmarking DONE Speed for cost 1 (t) of 1, cost 2 (m) of 1500, cost 3 (l) of 1 Many salts: 4114 c/s real, 4114 c/s virtual Only one salt: 4114 c/s real, 4151 c/s virtual none@...e ~/Desktop/r/run $ GWS=512 ./john --test --format=argon2d-opencl Benchmarking: argon2d-opencl [Blake2 OpenCL]... memory per hash : 1.46 MB Device 0: GeForce GTX 960M using different password for benchmarking DONE Speed for cost 1 (t) of 1, cost 2 (m) of 1500, cost 3 (l) of 1 Many salts: 4055 c/s real, 4096 c/s virtual Only one salt: 4096 c/s real, 4055 c/s virtual after this modification: none@...e ~/Desktop/r/run $ ./john --test --format=argon2d-opencl Benchmarking: argon2d-opencl [Blake2 OpenCL]... memory per hash : 1.46 MB Device 0: GeForce GTX 960M using different password for benchmarking DONE Speed for cost 1 (t) of 1, cost 2 (m) of 1500, cost 3 (l) of 1 Many salts: 4055 c/s real, 4055 c/s virtual Only one salt: 4055 c/s real, 4015 c/s virtual none@...e ~/Desktop/r/run $ GWS=512 ./john --test --format=argon2d-opencl Benchmarking: argon2d-opencl [Blake2 OpenCL]... memory per hash : 1.46 MB Device 0: GeForce GTX 960M using different password for benchmarking DONE Speed for cost 1 (t) of 1, cost 2 (m) of 1500, cost 3 (l) of 1 Many salts: 4055 c/s real, 4096 c/s virtual Only one salt: 4055 c/s real, 4055 c/s virtual
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.