Add 3s block time and change of block reward (#3469)

* Add 3s block time and change of block reward

* fixes

consensus/consensus_service.go

@@ -5,8 +5,6 @@ import (
 	"sync/atomic"
 	"time"
 
-	"github.com/harmony-one/harmony/internal/params"
-
 	"github.com/harmony-one/harmony/core/types"
 	"github.com/harmony-one/harmony/crypto/bls"
 
@@ -309,9 +307,9 @@ func (consensus *Consensus) UpdateConsensusInformation() Mode {
 
 	consensus.BlockPeriod = 5 * time.Second
 
-	// Disable aggregate sig at epoch TBD for mainnet (for other net, it's default to true)
-	if consensus.Blockchain.Config().ChainID == params.MainnetChainID && curEpoch.Cmp(big.NewInt(1000)) >= 0 {
-		consensus.AggregateSig = true
+	// Enable 3s block time at the threeSecondsEpoch
+	if consensus.Blockchain.Config().IsThreeSeconds(curEpoch) {
+		consensus.BlockPeriod = 3 * time.Second
 	}
 
 	isFirstTimeStaking := consensus.Blockchain.Config().IsStaking(nextEpoch) &&

internal/chain/reward.go

@@ -144,8 +144,9 @@ func AccumulateRewardsAndCountSigs(
 		bc.CurrentHeader().ShardID() == shard.BeaconChainShardID {
 		defaultReward := network.BaseStakedReward
 
-		// After block time is reduced to 5 seconds, the block reward is adjusted accordingly
+		// the block reward is adjusted accordingly based on 5s and 3s block time forks
 		if bc.Config().ChainID == params.TestnetChainID && bc.Config().FiveSecondsEpoch.Cmp(big.NewInt(16500)) == 0 {
+			// Testnet:
 			// This is testnet requiring the one-off forking logic
 			if blockNum > 634644 {
 				defaultReward = network.FiveSecondsBaseStakedReward
@@ -156,8 +157,16 @@ func AccumulateRewardsAndCountSigs(
 					}
 				}
 			}
-		} else if bc.Config().IsFiveSeconds(header.Epoch()) {
-			defaultReward = network.FiveSecondsBaseStakedReward
+			if bc.Config().IsThreeSeconds(header.Epoch()) {
+				defaultReward = network.ThreeSecondsBaseStakedReward
+			}
+		} else {
+			// Mainnet (other nets):
+			if bc.Config().IsThreeSeconds(header.Epoch()) {
+				defaultReward = network.ThreeSecondsBaseStakedReward
+			} else if bc.Config().IsFiveSeconds(header.Epoch()) {
+				defaultReward = network.FiveSecondsBaseStakedReward
+			}
 		}
 
 		// Following is commented because the new econ-model has a flat-rate block reward

internal/params/config.go

@@ -32,6 +32,7 @@ var (
 		PreStakingEpoch:   big.NewInt(185),
 		QuickUnlockEpoch:  big.NewInt(191),
 		FiveSecondsEpoch:  big.NewInt(230),
+		ThreeSecondsEpoch: big.NewInt(10000), // TBD
 		RedelegationEpoch: big.NewInt(290),
 		EIP155Epoch:       big.NewInt(28),
 		S3Epoch:           big.NewInt(28),
@@ -48,6 +49,7 @@ var (
 		PreStakingEpoch:   big.NewInt(1),
 		QuickUnlockEpoch:  big.NewInt(0),
 		FiveSecondsEpoch:  big.NewInt(16500),
+		ThreeSecondsEpoch: big.NewInt(70000),
 		RedelegationEpoch: big.NewInt(36500),
 		EIP155Epoch:       big.NewInt(0),
 		S3Epoch:           big.NewInt(0),
@@ -65,6 +67,7 @@ var (
 		PreStakingEpoch:   big.NewInt(1),
 		QuickUnlockEpoch:  big.NewInt(0),
 		FiveSecondsEpoch:  big.NewInt(0),
+		ThreeSecondsEpoch: big.NewInt(0),
 		RedelegationEpoch: big.NewInt(0),
 		EIP155Epoch:       big.NewInt(0),
 		S3Epoch:           big.NewInt(0),
@@ -82,6 +85,7 @@ var (
 		PreStakingEpoch:   big.NewInt(1),
 		QuickUnlockEpoch:  big.NewInt(0),
 		FiveSecondsEpoch:  big.NewInt(0),
+		ThreeSecondsEpoch: big.NewInt(0),
 		RedelegationEpoch: big.NewInt(0),
 		EIP155Epoch:       big.NewInt(0),
 		S3Epoch:           big.NewInt(0),
@@ -99,6 +103,7 @@ var (
 		PreStakingEpoch:   big.NewInt(1),
 		QuickUnlockEpoch:  big.NewInt(0),
 		FiveSecondsEpoch:  big.NewInt(0),
+		ThreeSecondsEpoch: big.NewInt(0),
 		RedelegationEpoch: big.NewInt(0),
 		EIP155Epoch:       big.NewInt(0),
 		S3Epoch:           big.NewInt(0),
@@ -115,6 +120,7 @@ var (
 		PreStakingEpoch:   big.NewInt(0),
 		QuickUnlockEpoch:  big.NewInt(0),
 		FiveSecondsEpoch:  big.NewInt(0),
+		ThreeSecondsEpoch: big.NewInt(0),
 		RedelegationEpoch: big.NewInt(0),
 		EIP155Epoch:       big.NewInt(0),
 		S3Epoch:           big.NewInt(0),
@@ -133,6 +139,7 @@ var (
 		big.NewInt(0),             // PreStakingEpoch
 		big.NewInt(0),             // QuickUnlockEpoch
 		big.NewInt(0),             // FiveSecondsEpoch
+		big.NewInt(0),             // ThreeSecondsEpoch
 		big.NewInt(0),             // RedelegationEpoch
 		big.NewInt(0),             // EIP155Epoch
 		big.NewInt(0),             // S3Epoch
@@ -151,6 +158,7 @@ var (
 		big.NewInt(0), // PreStakingEpoch
 		big.NewInt(0), // QuickUnlockEpoch
 		big.NewInt(0), // FiveSecondsEpoch
+		big.NewInt(0), // ThreeSecondsEpoch
 		big.NewInt(0), // RedelegationEpoch
 		big.NewInt(0), // EIP155Epoch
 		big.NewInt(0), // S3Epoch
@@ -204,6 +212,10 @@ type ChainConfig struct {
 	// and block rewards adjusted to 17.5 ONE/block
 	FiveSecondsEpoch *big.Int `json:"five-seconds-epoch,omitempty"`
 
+	// ThreeSecondsEpoch is the epoch when block time is reduced to 3 seconds
+	// and block rewards adjusted to 10.5 ONE/block
+	ThreeSecondsEpoch *big.Int `json:"three-seconds-epoch,omitempty"`
+
 	// RedelegationEpoch is the epoch when redelegation is supported and undelegation locking time
 	// is restored to 7 epoch
 	RedelegationEpoch *big.Int `json:"redelegation-epoch,omitempty"`
@@ -268,6 +280,11 @@ func (c *ChainConfig) IsFiveSeconds(epoch *big.Int) bool {
 	return isForked(c.FiveSecondsEpoch, epoch)
 }
 
+// IsThreeSeconds determines whether it is the epoch to change to 3 seconds block time
+func (c *ChainConfig) IsThreeSeconds(epoch *big.Int) bool {
+	return isForked(c.ThreeSecondsEpoch, epoch)
+}
+
 // IsRedelegation determines whether it is the epoch to support redelegation
 func (c *ChainConfig) IsRedelegation(epoch *big.Int) bool {
 	return isForked(c.RedelegationEpoch, epoch)

staking/network/reward.go

@@ -25,6 +25,11 @@ var (
 	FiveSecondsBaseStakedReward = numeric.NewDecFromBigInt(new(big.Int).Mul(
 		big.NewInt(17.5*denominations.Nano), big.NewInt(denominations.Nano),
 	))
+	// ThreeSecondsBaseStakedReward is the flat-rate block reward after epoch 360.
+	// 10.5 ONE per block
+	ThreeSecondsBaseStakedReward = numeric.NewDecFromBigInt(new(big.Int).Mul(
+		big.NewInt(10.5*denominations.Nano), big.NewInt(denominations.Nano),
+	))
 	// BlockRewardStakedCase is the baseline block reward in staked case -
 	totalTokens = numeric.NewDecFromBigInt(
 		new(big.Int).Mul(big.NewInt(12600000000), big.NewInt(denominations.One)),

staking/network/reward_test.go

@@ -14,4 +14,11 @@ func TestFiveSecondsBaseStakedReward(t *testing.T) {
 			"Expected: %s, Got: %s", FiveSecondsBaseStakedReward.String(), expectedNewReward.String(),
 		)
 	}
+
+	expectedNewReward = BaseStakedReward.Mul(numeric.MustNewDecFromStr("3")).Quo(numeric.MustNewDecFromStr("8"))
+	if !expectedNewReward.Equal(ThreeSecondsBaseStakedReward) {
+		t.Errorf(
+			"Expected: %s, Got: %s", ThreeSecondsBaseStakedReward.String(), expectedNewReward.String(),
+		)
+	}
 }