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Combinator attack slow down - Printable Version

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Combinator attack slow down - Wolfdale - 10-02-2014

Hi! I'm using the combinator attack with cudahashcat. I have a gtx 680. For MD5 bruteforce I get 2700 MH/s. If I try combinator attack with 2 dicts (20k words and 120M words) I get 1500MH/s (I believe it is because i'm not using any rule?)
The question is why towards the end it slows down to 1000 KH/s?

[Image: 2r46gbd.jpg]

Probably I'm doing something wrong, I've got alot to learn Tongue


RE: Combinator attack slow down - coolbry95 - 10-02-2014

Combinator attack is always going to be slower. Everything is slower than a mask attack.

OclHashcat slows down on purpose towards the end. It is adjusting the workload. Also I do not know if you are doing this or not, but the left dict needs to be larger than the left. The reason for this is the way GPGPU works.


RE: Combinator attack slow down - atom - 10-02-2014

It's also because with mask-attack (or general with brute-force) we can do some optimization because we know what comes "next". Therefore we can make use of meet-in-the-middle etc.