If two create_block_template are called at nearly the same time,
and a block is added at nearly the same time, this could happen:
- the blockchain top block is B0
- thread 1 enters create_block_template, takes blockchain lock
- thread 1 creates a fresh block referencing prev block B0
- thread 1 releases blockchain lock
- thread 0 adds a new block
- thread 0 enters create_block_template
- thread 0 updates block template
- thread 1 takes txpool lock and continues creating block template
- thread 1 overwrites block template with previous data
The change made for v2 broke v1, and we have no way to know which
version we're serializing here. However, since we don't actually
care about space savings in this case, we continue serialiazing
both mask and amount.
The 10 minute one will never trigger for 0 blocks, as it's still
fairly likely to happen even without the actual hash rate changing
much, so we add a 20 minute window, where it will (for 0 blocks)
and a one hour window.
This will trigger if a reorg is seen. This may be used to do things
like stop automated withdrawals on large reorgs.
%s is replaced by the height at the split point
%h is replaced by the height of the new chain
%n is replaced by the number of new blocks after the reorg
This curbs runaway growth while still allowing substantial
spikes in block weight
Original specification from ArticMine:
here is the scaling proposal
Define: LongTermBlockWeight
Before fork:
LongTermBlockWeight = BlockWeight
At or after fork:
LongTermBlockWeight = min(BlockWeight, 1.4*LongTermEffectiveMedianBlockWeight)
Note: To avoid possible consensus issues over rounding the LongTermBlockWeight for a given block should be calculated to the nearest byte, and stored as a integer in the block itself. The stored LongTermBlockWeight is then used for future calculations of the LongTermEffectiveMedianBlockWeight and not recalculated each time.
Define: LongTermEffectiveMedianBlockWeight
LongTermEffectiveMedianBlockWeight = max(300000, MedianOverPrevious100000Blocks(LongTermBlockWeight))
Change Definition of EffectiveMedianBlockWeight
From (current definition)
EffectiveMedianBlockWeight = max(300000, MedianOverPrevious100Blocks(BlockWeight))
To (proposed definition)
EffectiveMedianBlockWeight = min(max(300000, MedianOverPrevious100Blocks(BlockWeight)), 50*LongTermEffectiveMedianBlockWeight)
Notes:
1) There are no other changes to the existing penalty formula, median calculation, fees etc.
2) There is the requirement to store the LongTermBlockWeight of a block unencrypted in the block itself. This is to avoid possible consensus issues over rounding and also to prevent the calculations from becoming unwieldy as we move away from the fork.
3) When the EffectiveMedianBlockWeight cap is reached it is still possible to mine blocks up to 2x the EffectiveMedianBlockWeight by paying the corresponding penalty.
0 is placeholder for whole chain, so we should compare chain
height changes rather than chain-height-or-zero. Even this isn't
totally foolproof if a blocks are popped and the same number
added again, but it is much better as it prevents the data from
slowly going out of sync.
