Im also wondering that something must be wrong with this pool, surely statisticly variance cant be this bad over such an extensive period.
Sure its hashrate dropped from ~900GH avg to ~300GH avg since dropping from surplus to -1000coins most of the time but still this variance isnt even seen solomining like I am doing with part of my farm o_0
Ars employs a
nominal fee of 0%. The payout is based on 100% of found blocks being valid, but that's unlikely to happen in practice. In practice, some blocks turn out to be orphan blocks. The pool is taking a statistical hit of 50 BTC for every block that turns out to be an orphan, which is around 1.5% of all blocks for most pools.
The
effective fee is therefore about -1.5%. Yes, it's an effective bonus for miners! Who pays that bonus? The pool buffer. Total work done at Ars is now about 79850 BTC, which comes down to 1597 blocks. Although I can't find any orphan blocks in the stats at Ars, it's unlikely there haven't been any. You'd expect about 1.5%*1597 = 24 orphan blocks, causing a cumulative buffer drain of about 1200 BTC. The buffer is currently at -1000, not that far from -1200.
Now you may think: Great, the bonus is paid by the pool buffer, so I don't have to care about it. But the pool buffer is just a concept, and eventually real people have got to take the hit and accept the losses of all those orphan blocks. Who will those people be? It will be the last miners to quit Arsbitcoin. Since hashrate will then drop to 0, there's no new BTC flowing in. No income means the payouts for the last -BUFFER_SIZE Bitcoins can never be made.
In a sense, negative-effective-fee-SMPPS is not unlike the game "Musical chairs".
Until the moment the hashrate hits 0, the pool buffer will continue to drain at a rate of 1.5% of the theoretical PPS value of the delivered work, masked by normal variance in the block finding process. It is perfectly possible that due to normal variance the pool gets lucky and the buffer goes into positive territory again. Good and bad luck cancel each other out though, while the 1.5% drain is a constant negative force, creating ever longer payout delays.
Anyway..
For all reward schemes an effective fee can be calculated, and for PPS-derived schemes it differs from the nominal fee. At ABCPool there was some discussion when we started mentioning an effective fee in favor of a nominal fee; some vocal forum members found it to be misleading. Ars is now starting to show just how real the effective fee and its consequences are.
NB: ABCPool is *pure* PPS, there is no concept of a buffer for miners and therefore no payment delays.
