I've been tuning my L3's recently and I have a few questions I was hoping someone could clear up?
I will only try to answer those questions I'm relatively confident I can answer, as I don't have much hands-on experience with Antminers.
1) Are HW errors, rejected/stale shares, etc factored into the reported average hashrate on the miner's status page? In other words, if I have my miner clocked really fast but it's getting way to many HW errors, will it still report a really high hash rate or will it display an "effective" hash rate that is basically all the work done per unit time excluding HW errors?
I believe that HW errors and rejected shares are not factored into the hash rate reported by the miner. So if for example you have a lot of HW errors, the hash rate estimated by the pool will be much lower than the raw one reported by the miner.
4) What is the meaning of the Local Work, Utility, and WU fields?
Utility is shares submitted (either accepted or rejected, I believe) per minute. WU or Work Utility is the same thing but counting each share by its difficulty.
5) I always assumed the "best share" field is showing what the maximum network difficulty the best share/hash computed by the miner could have been if the miner were to have found a block. In other words, if the best share field read "500,000" then that would be like saying "If the network difficulty were 500,000, the best hash found would have satisfied the requirements to solve/create a new block". But I frequently see the best share field displaying a number substantially greater than actual global network difficulty. Is this because I misunderstand what that field means?
I think you essentially get it. I suspect the problem here is that this "best share" field is expressed as a share difficulty rather than a network difficulty. Due to historical reasons, in the case of coins using the scrypt algorithm, while network difficulty is expressed in the same way as Bitcoin's, share difficulty is expressed on a different scale. For instance, network difficulty 1 corresponds to a share difficulty of about 2
16.