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Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

rustyengines.silentmac.com

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Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#62

Post by petercooper »

rikfaith wrote: post #61
petercooper wrote: post #55

Someone on Twitter claimed this entry has already got the 0: http://twitter.com/rikfaith/statuses/2743945177 I have no way to check. True or not?

Just to be clear, I never claimed it got a 0 :)

Oh right, just someone I was following pointed to it and said it was. My bad :) (Well theirs, I guess.. :P)

Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#63

Post by silvio »

Would you be willing to write up the stats of your experiment once the challenge is over? I'd be really interested to know how much compute power you were able to harvest and what was the rate of compute acquisition.

Terrific idea and implementation. I have 10 tabs on Chrome. Good luck.

Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#64

Post by rikfaith »

petercooper wrote: post #62
rikfaith wrote: post #61

Earlier quoted context omitted.

Just to be clear, I never claimed it got a 0 :)

Oh right, just someone I was following pointed to it and said it was. My bad :) (Well theirs, I guess.. :P)

(The tweets I'm sending to contesttracker have the hamming distance at the front.)

Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#65

Post by Retric »

ErrantX wrote: post #34
mbrubeck wrote: post #14

Earlier quoted context omitted.

This JavaScript version: http://news.ycombinator.com/item?id=715014 (which doesn't do any throttling) is doing ~1500 hashes per second in one Chrome tab on my fairly old (2.8 GHz Pentium D) desktop. I'm curious how fast it would be on your Core 2 Duo in two Chrome tabs.

Mine peaked at 3,450 or so on a Core2 Quad @ 3.2Ghz

I think GPU's are going to win this "Yeah, my 5 GPUs are currently cranking at a total rate of 800 M/sec" they are are already looking at the low 30's.

Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#66

Post by ars »

silvio wrote: post #63

Would you be willing to write up the stats of your experiment once the challenge is over? I'd be really interested to know how much compute power you were able to harvest and what was the rate of compute acquisition. Terrific idea and implementation. I have 10 tabs on Chrome. Good luck.

He can't.

As far as I can tell, the browsers only contact him if they find a string with a shorter hamming distance, otherwise it's entirely offline, including picking random words.

Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#68

Post by jacquesm »

sil3ntmac wrote: post #30
judofyr wrote: post #26

Did you just get a hamming distance of 0, or is something broken?

Nah, some script kiddie messin with me. Fixed and patching the hole now...

a quicker approach to your bit counting routines: (in C because that's what I'm most comfortable with, but it is pretty much a drop-in replacement for your code)

  #include 

  char dist[256];

  hamm_init()

  {
        int i,j,n;

        for (i=0;i>= 1;    
                }

                dist[i] = n;
        }
  }

  int hamming_distance(char * hash1,char * hash2) {
        //calculate the distance between two hashes

        int d = 0;

        while (*hash1) {
                if (*hash2 == 0) {
                        break;
                }

                d += dist[*hash1++ ^ *hash2++];
        }

        return d;
  }

  main()

  {
        hamm_init();

        printf("0 %d\n",hamming_distance("abcd","abcd"));

        printf("1 %d\n",hamming_distance("accd","abcd"));

  }

Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#69

Post by jacquesm »

randomwalker wrote: post #60

Let's keep some perspective here folks. The idea is cool and all, but as discussed in the other thread, SHA-1 throughput on GPUs is between 200 million and 600 million per second, depending on the GPU ( http://forums.nvidia.com/index.php?s=&showtopic=102349&#... ). On the other hand, the maximum throughput that people are getting with JS is about 3000/second. Which is a hundred thousand times slower. I think it is sa…

That's true and it was my first thought (which is why I asked about benchmarking the js code). What it did do was to get a pretty clever idea out into the world, which is to crowdsource the answer to some contest.

Contests are usually held to fire up peoples creativity and this idea to solve it via the browser as an ad-hoc cluster is really pretty creative.

Personally I think to try to solve this contest by brute forcing it is changing it in to a simple pissing contest between the various hardware / software combination, I'm sure some guy with an fpga kit will do a lot better than the CUDA competitors.

It would be nicer if someone discovered a previously undetected flaw and solved the contest through a backdoor. that would be hacker news :)

Re: Crowdsourcing Bruteforcing: Help me win the EngineYard challenge

#70

Post by sp332 »

rarestblog wrote: post #48
sil3ntmac wrote: post #40

Earlier quoted context omitted.

Updated to 1ms! I'll work on the HTML stat updates Edit: fixed and fixed

You might also consider removing UTF8Encoding from SHA1 implementation, I might be wrong, but I think contest states no encoding should be used - i.e. ASCII only. If that's a care, that's a useless O(N) operation.

UTF8(ASCII) == ASCII

Unless you're using characters > 255, UTF-8 is identical to ASCII.

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