pools hash rate VS miner hash rate

[zhangxiongfei]

Hi there

I was mining on some popular pools such as btcguild/slush/deepbit. My miners were Icarus FPGA boards with cgminer. 
why is the hash rate i saw on pool website so different from the hash rate listed by "cgminer-api devs"?

thanks
xiongfei

[Chi11ed]

This is a good question. I also get these differences with my 6990. I get a constant rate of 750mhash, but have seen my online worker rate around 850 at times, then at 650 etc. I guess it averages out but still its weird.

[holgerr]

It's because the pools estimate your hash rate based on submitted shares, while your cgminer has access to the actual hash rate. So if you're lucky and find a lot of shares quickly with your constant hash rate, the pool will think you are hashing faster, while if you're a bit unlucky and don't find as many shares for a while, it will think you're hashing slower. As you said, it all evens out over time. If it doesn't, maybe you're creating a lot of invalid/stale shares.

[zhangxiongfei]

It's because the pools estimate your hash rate based on submitted shares, while your cgminer has access to the actual hash rate. So if you're lucky and find a lot of shares quickly with your constant hash rate, the pool will think you are hashing faster, while if you're a bit unlucky and don't find as many shares for a while, it will think you're hashing slower. As you said, it all evens out over time. If it doesn't, maybe you're creating a lot of invalid/stale shares.

Thanks for your explanation.
Is it possible to solve this problem ? Is this all about being lucky?

[heropzy]

Same question I want to ask.

[Pheal]

It's because the pools estimate your hash rate based on submitted shares, while your cgminer has access to the actual hash rate. So if you're lucky and find a lot of shares quickly with your constant hash rate, the pool will think you are hashing faster, while if you're a bit unlucky and don't find as many shares for a while, it will think you're hashing slower. As you said, it all evens out over time. If it doesn't, maybe you're creating a lot of invalid/stale shares.

Thanks for your explanation.
Is it possible to solve this problem ? Is this all about being lucky?

I think it's to avoid people sending fake hashing speeds. It is always better to estimate it on valid shares since that cannot really be faked.