Tesla K20m sha512crypt dictionary attack performance issues
#3
this is a salted algorithm and you have 10 salts, so your effective speed will be 10x slower than if you were cracking a single hash. 2533 H/s * 10 = 25330 H/s which is damn close to your benchmark value of 25511 H/s. so your performance is pretty close to the maximum performance under ideal conditions. you could squeeze a bit more performance out of it if you set gpu-loops to 5000, since sha512crypt is iterated 5000 times.

i'm not entirely sure why it's using that much cpu, but as you said the load avg is only 400 and not 800, so you are not cpu bound.

regarding the benchmark of the other system you posted... that was from several months ago, so that was likely using a different driver. i know several users have complained about large speed drops with newer nvidia drivers, so that could be part of the problem. other thing to consider is that those benchmarks were made with oclHashcat-lite, which does not exist anymore. the functionality of that product was rolled into oclHashcat, and while there was not much performance impact for most algorithms on AMD, i have no idea how nvidia was affected. so that could be part of the issue as well, but i do not know for sure.

can't really complain about the speed with your hardware, though. if you wanted it to be fast, you shouldn't have bought nvidia cards Smile


Messages In This Thread
RE: Tesla K20m sha512crypt dictionary attack performance issues - by epixoip - 02-24-2014, 01:50 PM