Quote from: mjosephs on July 20, 2017, 01:43:36 AM

Quote from: D8V1D on July 20, 2017, 12:26:46 AM

Had something weird happen. Got 45.19 for finding one block.
Anyone had this happen before?

Yes, when the difficulty is falling a small number of the blocks come with a larger block reward.

This prevents large sources of hashrate (like nicehash) from "coin hopping".

Coin hopping is a lot like the "pool hopping" scheme that was commonplace before PPLNS, but instead of switching pools you switch coins. It is a problem for every GPU-mined coin. No matter how fancy and clever the difficulty-adjustment algorithm is, if there any large single source of hashpower (cough cough nicehash) they can boost their income by jumping into a coin, mining until the difficulty catches up to their added hashrate, then jumping over to another coin. Even if the difficulty adjusts in one block, they still got mined one block of low-difficulty using their high hashrate. As long as there are enough coins to hop between they can hop on every block, doesn't matter how fast the difficulty adjusts since it is always based on the previous block(s). Take a look at the Monero hashrate, it's been oscillating up and down with almost exactly a 24-hour period for a few years now (their difficulty adjustment window is based on the last 24 hours worth of blocks).

By giving more reward to a randomly chosen block during dropping-difficulty periods (which is effectively taken from the reward during rising-difficulty periods) nexus thwarts this exploit. Well, in theory. It looks like the formula for boosting the reward is messed up, the bonus blocks seem to be larger and less frequent than they should be, but it still helps. The other drawback is that this only works for multi-algorithm coins where the network time is based on all mining algorithms. If a single-algorithm coin tried to do this then a nicehash-like coin hopper could defeat the mechanism by screwing with the block timestamps, and with enough hashpower the chain wouldn't know they were fudging the timestamps (by a small amount) and making the chain think the difficulty was dropping (by speeding up time) when in fact it wasn't. Everybody would do this and pretty soon the chain timestamps would be way ahead of the actual wall-clock time on all the non-mining clients.

With two or more mining algorithms there is no incentive for the miners on the other algorithms to do the same thing at the same time, so they don't. On the other hand nexus's "unified time" causes a lot of other headaches for people, I'm not sure it was a good idea either.

Actually the block reward varies to meet strict emission schedule, when the reserves fall above or below certain levels the block reward adjusts to ensure emissions stay on target. If blocks are found to quickly for a specific channel the reserves become depleted and the block reward gets reduced. When blocks are found to slowly for a particular channel the reserves build and block reward increases.

Quote from: Squall10 on July 20, 2017, 03:03:53 AM

I found two blocks today but only one get credited: the other one is gone !

I found 9 blocks in total but my balance is 108,591633 (a balance of 8 blocks)

Edit : the nb of transactions was 9 and it is 8 now...

The "missing block" is likely to have been an orphan, you can check this by going to the debug console and entering listtransactions
if you need to search more than the default number of transactions displayed listtransactions '' 100 will show the last 100 transactions. Note its 2 ' ' not a single ".

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