Merge pull request bnb-chain#59 from node-real/improve-block-proposer-layer-liveness

imporve liveness of block proposal layer

Author: NathanBSC

consensus/parlia/parlia.go

@@ -389,14 +389,6 @@ func getVoteAttestationFromHeader(header *types.Header, chainConfig *params.Chai
 	return &attestation, nil
 }
 
-func getSignRecentlyLimit(blockNumber *big.Int, validatorsNumber int, chainConfig *params.ChainConfig) int {
-	limit := validatorsNumber/2 + 1
-	if chainConfig.IsBoneh(blockNumber) {
-		limit = cmath.CeilDiv(validatorsNumber*2, 3)
-	}
-	return limit
-}
-
 // verifyVoteAttestation checks whether the vote attestation in the header is valid.
 func (p *Parlia) verifyVoteAttestation(chain consensus.ChainHeaderReader, header *types.Header, parents []*types.Header) error {
 	attestation, err := getVoteAttestationFromHeader(header, p.chainConfig, p.config)
@@ -757,7 +749,7 @@ func (p *Parlia) verifySeal(chain consensus.ChainHeaderReader, header *types.Hea
 	for seen, recent := range snap.Recents {
 		if recent == signer {
 			// Signer is among recents, only fail if the current block doesn't shift it out
-			if limit := getSignRecentlyLimit(header.Number, len(snap.Validators), p.chainConfig); seen > number-uint64(limit) {
+			if limit := uint64(len(snap.Validators)/2 + 1); seen > number-limit {
 				return errRecentlySigned
 			}
 		}
@@ -1291,7 +1283,7 @@ func (p *Parlia) Seal(chain consensus.ChainHeaderReader, block *types.Block, res
 	for seen, recent := range snap.Recents {
 		if recent == val {
 			// Signer is among recents, only wait if the current block doesn't shift it out
-			if limit := getSignRecentlyLimit(header.Number, len(snap.Validators), p.chainConfig); number < uint64(limit) || seen > number-uint64(limit) {
+			if limit := uint64(len(snap.Validators)/2 + 1); number < limit || seen > number-limit {
 				log.Info("Signed recently, must wait for others")
 				return nil
 			}
@@ -1406,8 +1398,7 @@ func (p *Parlia) SignRecently(chain consensus.ChainReader, parent *types.Block)
 		}
 
 		// Signer is among recents, only wait if the current block doesn't shift it out
-		limit := getSignRecentlyLimit(parent.Number(), len(snap.Validators), p.chainConfig)
-		if number < uint64(limit) || seen > number-uint64(limit) {
+		if limit := uint64(len(snap.Validators)/2 + 1); number < limit || seen > number-limit {
 			return true, nil
 		}
 	}
@@ -1849,7 +1840,7 @@ func (p *Parlia) backOffTime(snap *Snapshot, header *types.Header, val common.Ad
 
 		// Exclude the recently signed validators first, and then compute the backOffTime.
 		recentVals := make(map[common.Address]struct{}, len(snap.Recents))
-		limit := getSignRecentlyLimit(header.Number, len(snap.Validators), p.chainConfig)
+		limit := len(snap.Validators)/2 + 1
 		for seen, recent := range snap.Recents {
 			if header.Number.Uint64() < uint64(limit) || seen > header.Number.Uint64()-uint64(limit) {
 				if val == recent {

consensus/parlia/snapshot.go

@@ -219,8 +219,8 @@ func (s *Snapshot) apply(headers []*types.Header, chain consensus.ChainHeaderRea
 	for _, header := range headers {
 		number := header.Number.Uint64()
 		// Delete the oldest validator from the recent list to allow it signing again
-		if limit := getSignRecentlyLimit(header.Number, len(snap.Validators), chainConfig); number >= uint64(limit) {
-			delete(snap.Recents, number-uint64(limit))
+		if limit := uint64(len(snap.Validators)/2 + 1); number >= limit {
+			delete(snap.Recents, number-limit)
 		}
 		if limit := uint64(len(snap.Validators)); number >= limit {
 			delete(snap.RecentForkHashes, number-limit)
@@ -261,8 +261,8 @@ func (s *Snapshot) apply(headers []*types.Header, chain consensus.ChainHeaderRea
 					}
 				}
 			}
-			oldLimit := getSignRecentlyLimit(header.Number, len(snap.Validators), chainConfig)
-			newLimit := getSignRecentlyLimit(header.Number, len(newVals), chainConfig)
+			oldLimit := len(snap.Validators)/2 + 1
+			newLimit := len(newVals)/2 + 1
 			if newLimit < oldLimit {
 				for i := 0; i < oldLimit-newLimit; i++ {
 					delete(snap.Recents, number-uint64(newLimit)-uint64(i))