Six Second Block Time

I was wondering how the Block time was at 6 seconds for awhile?. I had thought it was roughly 6 minutes. The Pool hashrate was 20+ MH/s and the difficulty never changed. As far as I noticed it went on for about 15 or so minutes. I don’t know if it would be considered an attack on the network. Forgive me if this is a noob question, it just seemed weird.


As Safex is a Cryptonight based blockchain, it has a difficulty rating based on averages.

The algorithm examines the past 720 blocks, starting from 15 blocks previous to the current block. Out of these blocks, 60 of the highest and lowest blocks are excluded from the calculation, which leaves 600 blocks.

Out of THESE 600 blocks, the average block time is determined. The average is then used to adjust the difficulty score in order to reach our target block time of 120 seconds (2 mins). The difficulty is defined as the number of hash attempts required, on average, to find the valid hash for the block every 120 seconds.

When you face a sudden spike in hash rate, such as the 20MH/s one you saw earlier, it would take at least 75 blocks (15 + 60) before changes in the hashrate are seen in the difficulty score. Therefore, the difficulty adjustment is gradual.

It would take 675 blocks (15 + 60 + 600) for that 20MH/s to be fully realised on the blockchain.

You do see spikes in network hash rate on pools from time to time. Normally it comes from Nicehash miners.

I wouldn’t straight away assume that whoever is doing this mining is doing it for suspicious reasons. In some cases, it could be as simple as a wrongly configured NiceHash order, or the miner may be inexperienced and assume more hash rate = better gains. You certainly don’t need to mine at 4-5x the network hash rate to earn yourself a decent return.

Sometimes, when a miner sees a drastic drop in network hash rate, they take advantage of the easier mining opportunity and order some nicehash power.

I think this is as good of a time to release the two new tools i’ve added to Safex News:

Difficulty History:
Hashrate History:

Hope this explains it all to you!

PS: Bonus Info - The Network Hashrate is calculated by taking the current difficulty score and dividing it by the target block time, 120.


Thank You for taking the time to respond. You answered my question and then some. I definetly want to more about mining and how it all really works and your answer explains a lot.