Quote from: Wh1teKn1ght on March 27, 2014, 09:59:13 PM

Thanks for the responses. Can you explain though why/how short block times encourage centralization of hashing power? I don't understand this statement. Thanks!

Let's say we have a network propogation time of around 10 seconds for a newly mined block at one "side" of the network to fully propogate so the vast majority of other nodes have that block.

With VTC, every 2.5 minutes (on average), there's a window of opportunity 10 seconds long for a pool (or a big solominer, lol@him) to find a valid, but stale block. That is 10/150=0.066 so around 6.5% of the time - that will be the baseline stale ratio for the network.

Let's say a (too big) pool has 25% of nethash. Since it doesn't need to wait for blocks _it_ found to be relayed, so can start working on the next one right away without waiting, it gets a (small) efficiency boost - it has to wait for relaying 75% of the time, so 0.75*6.5=4.9% is that pools stale ratio - it's efficiency is 95.1% as opposed to 93.5% for the network as a whole, so it gets a 95.1/93.5 - 1 = 1.7% advantage.

With the 45 second block time that EXE uses, the baseline stale ratio is 10/45=22% - now our big pool with 25% of nethash has a 0.75*22=16.5% stale ratio, 5.5% better than the network as a whole, and has 83.5% efficiency vs. 78% for the network, so is 83.5/78 - 100 = 7% advantage over the network as a whole, compared to the relatively insignificant 1.7% for the 2.5 minute blocktime of VTC.

So very short blocktimes waste more of miners work, but they also encourage centralisation.

BTW while we're on the subject, can some of you check out http://www.reddit.com/r/vertcoin/comments/21imwo/consider_mining_on_2nd_p2pool_network_to_allow/ - it is for those of you with lower hashrate who were finding p2pool difficult to find shares on in time to get them counted in a block, and should drastically improve things. Please don't move over if you're a bigger hasher - it would be best to get a lot of smaller hashers on p2pool2 to get them to a workable mix of blockrate and sharerate.

Oh and check out - http://www.verters.com/block-analysis - WELL DONE! it's fantastic to see that so many people have got the word out and helped spread the hashrate around in so short a time! I only started banging on about this 2 days ago and already I can stop! Thankyou all, keep it up, but now there's really no need for many of you to consider moving (although a small few could still move from vertco.in), all the pools are under 20% of nethash, it would be nice to keep them that way (apart from p2pool which can get as big as it wants, and even then is now divided in 2)