Bitcoin Forum

Bitcoin => Mining => Topic started by: Tx2000 on July 18, 2011, 10:18:10 PM



Title: Hash/Share question
Post by: Tx2000 on July 18, 2011, 10:18:10 PM
I've been monitoring my hashing and shares more closely and it sort of dawned on me that Mhash does not necessarily translate into a share.  More clearly, X Mhash does not guarantee Y amount of shares within Z amount of time.  Is this correct?

example only: 100Mhash equals 1 share every second.  So 1 minute would always yield 60 shares


I've noticed some rounds, let's say under 2 minutes, I was not able to able to get any shares submitted.  But another, under 1 minute, I was able to get 6 shares submitted.




Title: Re: Hash/Share question
Post by: nebiki on July 18, 2011, 10:59:58 PM
it's not correct. 1 share = a hash which would have generated a block if difficulty were 1. that's where your variance comes from, too. someone here (search "pool mathematics" or something) calculated the rate to be around 71.5 mhash/s for 1 share/min.

edit: i've had a nice table which showed my expected shares and actual earned shares using this conversion rate. it was about the same (>98% after 2 days). i did this to monitor the pool uptime.


Title: Re: Hash/Share question
Post by: pilardi on July 18, 2011, 11:16:59 PM
I've been monitoring my hashing and shares more closely and it sort of dawned on me that Mhash does not necessarily translate into a share.  More clearly, X Mhash does not guarantee Y amount of shares within Z amount of time.  Is this correct?

example only: 100Mhash equals 1 share every second.  So 1 minute would always yield 60 shares


I've noticed some rounds, let's say under 2 minutes, I was not able to able to get any shares submitted.  But another, under 1 minute, I was able to get 6 shares submitted.




It takes on average 2^32 hashes to get a share.  So it takes roughly 10 seconds to generate a share on a 6970 (420MH/s).  This is a random process, so it will vary, but over the long term, it should average to 2^32 hashes per share.  So it would take about 4.2GH/s to average 60 shares per minute.

It will take on average "difficulty" number of shares to generate a block.

See this for more:
https://en.bitcoin.it/wiki/Difficulty#How_soon_might_I_expect_to_generate_a_block.3F


Title: Re: Hash/Share question
Post by: nebiki on July 19, 2011, 12:37:21 AM
I've been monitoring my hashing and shares more closely and it sort of dawned on me that Mhash does not necessarily translate into a share.  More clearly, X Mhash does not guarantee Y amount of shares within Z amount of time.  Is this correct?

example only: 100Mhash equals 1 share every second.  So 1 minute would always yield 60 shares


I've noticed some rounds, let's say under 2 minutes, I was not able to able to get any shares submitted.  But another, under 1 minute, I was able to get 6 shares submitted.




It takes on average 2^32 hashes to get a share.  So it takes roughly 10 seconds to generate a share on a 6970 (420MH/s).  This is a random process, so it will vary, but over the long term, it should average to 2^32 hashes per share.  So it would take about 4.2GH/s to average 60 shares per minute.

It will take on average "difficulty" number of shares to generate a block.

See this for more:
https://en.bitcoin.it/wiki/Difficulty#How_soon_might_I_expect_to_generate_a_block.3F


i won't answer anything anymore. some random people keep popping up and say the exact same thing. that's boring