FTC Block Time Analysis
Methodology and spreadsheet for graphical analysis of Bitcoin-abe Blockchain explorer output
2016-05-31 FTC Transaction Block time and difficulty adjustment Analysis
Spreadsheet and charts from an analysis of the Feathercoin Blockchain for 100 Hours and over 2 Days. The resulting charts show the variation of the Difficulty and Time between blocks.
The FTC algorithm was designed to efficiently adjust the difficulty to account for rapid changes in Hash rate available to the network was switched between "multi-pools". Currently there is no problem with multi-pools but the move to more distributed mining and the simplification of using NSGminer has meant that it is possible to build a large rig with GPUs and control a large portion of the block transactions. It is important to see how the algorithm reacts.
Data was extracted from the publicly available Feathercoin Blockchain Explorer, the following command was used in the browser to increase the number of records. That was cut and paste into a text editor to text format it, then pasted into the analysis spreadsheet.
Transaction Value compared to Fees and Percentage blocks with a Transaction
Three days Blockchain data have been analysed in detail.
Value of Transactions 58 times Value of Fees
Percentage Blocks with transactions 28%
Value of Transactions 38 times Value of Fees
Percentage Blocks with transactions 29%
Value of Transactions 5 times Value of Fees
Percentage Blocks with transactions 29%
Short term analysis over 100 minutes
This chart shows how the difficulty adjusted during a 500% variation in FTC Hash rate. The blue diagonal line shows the block frequency against time. This should be a straight diagonal line in ideal situation.
It was noted that some blocks had reverse timing, this is due to the high hash and does not necessarily mean an error. The block are pre - created, so the next block can start to be created before the previous block is confirmed. This is not necessarily good for the high hasher as they must the be following various chains into the future.
It may be that the current cycling nature is due to the variation being over 100%, the high hasher runs out of future blocks to mine.
It may also be that some pools do not have their time set correctly.
The red line shows the reaction of the difficulty. Although there is always going to be a slight delay to reaction it appears to be as specified and successfully increasing and reducing the Difficulty. The cycles show are 20 mins of hash rate of 400% normal.
Analysis of TheBlockFactory showed it has a FTC Hash rate of 204 MHash/s compared to Overall FTC Hash rate of 654 MHash/s and "core p2pool" 10 - 50 MHash/s.
However, it would apparently need 3 * 654 or 2,500 MHash/s to produce some of the variations in Hash rate observed.
FTC Difficulty variation 31/05/2016
The second chart shows the Time between blocks during a period of extreme hash rate change. FTC eHRC (Hash Rate Compensation) algorithm adjust the difficulty as hash changes to maintain a one minute block time. Here the green line shows the time between each block, the red line shows the average trend of time for the period. Although when the high hash switches in time between block are low, it does quickly start to compensate and bring the block time back.
Generally the high block times are last bellow 2 minutes although one block does take 8 minutes at these extreme levels.
A rough calibration of MHash/s per Difficulty 9 = 650 MHash/s, or 72 MHash per 1 Difficulty.
The Difficulty is seen to vary from 5 to 13, indicates a variation of global FTC hash rate from 400 HMash/s to 940 MHash/s. That is a variation of 500 MHash/s
FTC short term Block time variation 31/05/2016
FTC Medium term Difficulty variation 31/05/2016
This chart shows the difficulty medium term, over a couple of days. The maximum Difficulty is 25, with an average of about 10. The blue line shows the block height increasing, the straighter that line is, the more regular the block production.
The block times are scattered around the average, just above one minute.
FTC medium term Block time variation 31/05/2016
This chart show the block times over a couple of days scaled to show the one minute detail.
FTC Scaled - medium term Block time variation 31/05/2016
The Difficulty is seen to vary from 5 to 10, indicates a variation of global FTC hash rate from 400 HMash/s to 800 MHash/s. That is a variation of 400 MHash/s
2016-06-01 24 Hour - FTC Transaction Block time and difficulty adjustment Analysis
FTC Difficulty variation 01/06/2016
FTC short term Block time variation 01/06/2016
The short term analysis for the 01/06/2016 shows some variation in difficulty, not as extreme as 31st. It can also be seen that the blue diagonal - 1 minute line is straighter, showing the diagonal is an indicator of hash stability.
The high hash rate variability being experienced by FTC Blockchain, is producing excess short time blocks, which is being compensated by eHRC holding the average above 1 minute. For reviewing historical trends and future changes, the level above 1 minute indicate the extent eHRC is "damped" of delayed in action and will vary proportional to the hash rate variation.
Although it would probably have a minimal effect, removing the difficulty damping and changing the short term average from 15 to 13 blocks, as originally specified for eHRC, would give a quicker response to FTC hash variations.
Increasing the log term average to the original specification 2000 blocks would also help prevent the block time disparity dropping of the average time of the eHRC calculation.
FTC Medium term Difficulty variation 01/06/2016
The chart shows the difficulty variation over ~24 hours, 1800 transactions. For this period, on the 1st June 2016, the maximum Difficulty was 17 and the average was 8. The variation and peak levels being less than the 31st, the variation of hash was less as well, being between 5 and 12.
FTC medium term Block time variation 01/06/2016
FTC Scaled - medium term Block time variation 01/06/2016
2016-06-06 24 Hour - FTC Transaction Block time and difficulty adjustment Analysis
FTC Difficulty variation 06/06/2016
FTC short term Block time variation 06/06/2016
FTC Medium term Difficulty variation 06/06/2016
For this 24 Hour period on 6th June 2016 the peak difficulty was 19, the average is 7. The variation in difficulty was generally between 4 and 10.
FTC medium term Block time variation 06/06/2016