miner: gas limit strategy, target 3141592 & def gas price 50 Shannon

This commit is contained in:
Gustav Simonsson
2015-08-03 02:46:34 +02:00
parent ff66e8fa29
commit 26c6e3b206
4 changed files with 22 additions and 8 deletions

View File

@ -69,17 +69,30 @@ func CalcTD(block, parent *types.Block) *big.Int {
// CalcGasLimit computes the gas limit of the next block after parent.
// The result may be modified by the caller.
// This is miner strategy, not consensus protocol.
func CalcGasLimit(parent *types.Block) *big.Int {
decay := new(big.Int).Div(parent.GasLimit(), params.GasLimitBoundDivisor)
// contrib = (parentGasUsed * 3 / 2) / 1024
contrib := new(big.Int).Mul(parent.GasUsed(), big.NewInt(3))
contrib = contrib.Div(contrib, big.NewInt(2))
contrib = contrib.Div(contrib, params.GasLimitBoundDivisor)
// decay = parentGasLimit / 1024 -1
decay := new(big.Int).Div(parent.GasLimit(), params.GasLimitBoundDivisor)
decay.Sub(decay, big.NewInt(1))
/*
strategy: gasLimit of block-to-mine is set based on parent's
gasUsed value. if parentGasUsed > parentGasLimit * (2/3) then we
increase it, otherwise lower it (or leave it unchanged if it's right
at that usage) the amount increased/decreased depends on how far away
from parentGasLimit * (2/3) parentGasUsed is.
*/
gl := new(big.Int).Sub(parent.GasLimit(), decay)
gl = gl.Add(gl, contrib)
gl = gl.Add(gl, big.NewInt(1))
gl.Set(common.BigMax(gl, params.MinGasLimit))
// however, if we're now below the target (GenesisGasLimit) we increase the
// limit as much as we can (parentGasLimit / 1024 -1)
if gl.Cmp(params.GenesisGasLimit) < 0 {
gl.Add(parent.GasLimit(), decay)
gl.Set(common.BigMin(gl, params.GenesisGasLimit))