core: vm: automatically calculate notary set size (#276)

7 files changed, 125 insertions, 44 deletions

diff --git a/core/governance.go b/core/governance.go
index db0e60b6c..da310a1cd 100644
--- a/core/governance.go
+++ b/core/governance.go
@@ -99,7 +99,7 @@ func (g *Governance) Configuration(round uint64) *coreTypes.Config {
 	return &coreTypes.Config{
 		LambdaBA:         time.Duration(c.LambdaBA) * time.Millisecond,
 		LambdaDKG:        time.Duration(c.LambdaDKG) * time.Millisecond,
-		NotarySetSize:    c.NotarySetSize,
+		NotarySetSize:    uint32(configHelper.NotarySetSize().Uint64()),
 		DKGSetSize:       c.DKGSetSize,
 		RoundLength:      c.RoundLength,
 		MinBlockInterval: time.Duration(c.MinBlockInterval) * time.Millisecond,
diff --git a/core/vm/oracle_contract_abi.go b/core/vm/oracle_contract_abi.go
index 369c9ec17..af0affece 100644
--- a/core/vm/oracle_contract_abi.go
+++ b/core/vm/oracle_contract_abi.go
@@ -141,6 +141,20 @@ const GovernanceABIJSON = `
   {
     "constant": true,
     "inputs": [],
+    "name": "notaryParamBeta",
+    "outputs": [
+      {
+        "name": "",
+        "type": "uint256"
+      }
+    ],
+    "payable": false,
+    "stateMutability": "view",
+    "type": "function"
+  },
+  {
+    "constant": true,
+    "inputs": [],
     "name": "miningVelocity",
     "outputs": [
       {
@@ -196,6 +210,20 @@ const GovernanceABIJSON = `
   },
   {
     "constant": true,
+    "inputs": [],
+    "name": "notaryParamAlpha",
+    "outputs": [
+      {
+        "name": "",
+        "type": "uint256"
+      }
+    ],
+    "payable": false,
+    "stateMutability": "view",
+    "type": "function"
+  },
+  {
+    "constant": true,
     "inputs": [
       {
         "name": "",
@@ -817,11 +845,11 @@ const GovernanceABIJSON = `
         "type": "uint256"
       },
       {
-        "name": "NotarySetSize",
+        "name": "NotaryParamAlpha",
         "type": "uint256"
       },
       {
-        "name": "DKGSetSize",
+        "name": "NotaryParamBeta",
         "type": "uint256"
       },
       {
diff --git a/core/vm/oracle_contracts.go b/core/vm/oracle_contracts.go
index b8eb4fedc..e30d0382a 100644
--- a/core/vm/oracle_contracts.go
+++ b/core/vm/oracle_contracts.go
@@ -21,6 +21,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"math"
 	"math/big"
 	"sort"
 
@@ -84,6 +85,8 @@ const (
 	lambdaBALoc
 	lambdaDKGLoc
 	notarySetSizeLoc
+	notaryParamAlphaLoc
+	notaryParamBetaLoc
 	dkgSetSizeLoc
 	roundLengthLoc
 	minBlockIntervalLoc
@@ -816,11 +819,43 @@ func (s *GovernanceState) LambdaDKG() *big.Int {
 func (s *GovernanceState) NotarySetSize() *big.Int {
 	return s.getStateBigInt(big.NewInt(notarySetSizeLoc))
 }
+func (s *GovernanceState) CalNotarySetSize() {
+	nodeSetSize := float64(len(s.QualifiedNodes()))
+	setSize := math.Ceil((nodeSetSize*0.6-1)/3)*3 + 1
+
+	if nodeSetSize >= 80 {
+		alpha := float64(s.NotaryParamAlpha().Uint64()) / decimalMultiplier
+		beta := float64(s.NotaryParamBeta().Uint64()) / decimalMultiplier
+		setSize = math.Ceil(alpha*math.Log(nodeSetSize) - beta)
+	}
+	s.setStateBigInt(big.NewInt(notarySetSizeLoc), big.NewInt(int64(setSize)))
+}
+
+// uint256 public notaryParamAlpha;
+func (s *GovernanceState) NotaryParamAlpha() *big.Int {
+	return s.getStateBigInt(big.NewInt(notaryParamAlphaLoc))
+}
+
+// uint256 public notaryParamBeta;
+func (s *GovernanceState) NotaryParamBeta() *big.Int {
+	return s.getStateBigInt(big.NewInt(notaryParamBetaLoc))
+}
 
 // uint256 public dkgSetSize;
 func (s *GovernanceState) DKGSetSize() *big.Int {
 	return s.getStateBigInt(big.NewInt(dkgSetSizeLoc))
 }
+func (s *GovernanceState) CalDKGSetSize() {
+	nodeSetSize := float64(len(s.QualifiedNodes()))
+	setSize := math.Ceil((nodeSetSize*0.6-1)/3)*3 + 1
+
+	if nodeSetSize >= 100 {
+		alpha := float64(s.NotaryParamAlpha().Uint64()) / decimalMultiplier
+		beta := float64(s.NotaryParamBeta().Uint64()) / decimalMultiplier
+		setSize = math.Ceil(alpha*math.Log(nodeSetSize) - beta)
+	}
+	s.setStateBigInt(big.NewInt(dkgSetSizeLoc), big.NewInt(int64(setSize)))
+}
 
 // uint256 public roundLength;
 func (s *GovernanceState) RoundLength() *big.Int {
@@ -939,8 +974,8 @@ func (s *GovernanceState) Configuration() *params.DexconConfig {
 		BlockGasLimit:     s.getStateBigInt(big.NewInt(blockGasLimitLoc)).Uint64(),
 		LambdaBA:          s.getStateBigInt(big.NewInt(lambdaBALoc)).Uint64(),
 		LambdaDKG:         s.getStateBigInt(big.NewInt(lambdaDKGLoc)).Uint64(),
-		NotarySetSize:     uint32(s.getStateBigInt(big.NewInt(notarySetSizeLoc)).Uint64()),
-		DKGSetSize:        uint32(s.getStateBigInt(big.NewInt(dkgSetSizeLoc)).Uint64()),
+		NotaryParamAlpha:  float32(s.getStateBigInt(big.NewInt(notaryParamAlphaLoc)).Uint64()) / decimalMultiplier,
+		NotaryParamBeta:   float32(s.getStateBigInt(big.NewInt(notaryParamBetaLoc)).Uint64()) / decimalMultiplier,
 		RoundLength:       s.getStateBigInt(big.NewInt(roundLengthLoc)).Uint64(),
 		MinBlockInterval:  s.getStateBigInt(big.NewInt(minBlockIntervalLoc)).Uint64(),
 		FineValues:        s.FineValues(),
@@ -958,11 +993,15 @@ func (s *GovernanceState) UpdateConfiguration(cfg *params.DexconConfig) {
 	s.setStateBigInt(big.NewInt(blockGasLimitLoc), big.NewInt(int64(cfg.BlockGasLimit)))
 	s.setStateBigInt(big.NewInt(lambdaBALoc), big.NewInt(int64(cfg.LambdaBA)))
 	s.setStateBigInt(big.NewInt(lambdaDKGLoc), big.NewInt(int64(cfg.LambdaDKG)))
-	s.setStateBigInt(big.NewInt(notarySetSizeLoc), big.NewInt(int64(cfg.NotarySetSize)))
-	s.setStateBigInt(big.NewInt(dkgSetSizeLoc), big.NewInt(int64(cfg.DKGSetSize)))
+	s.setStateBigInt(big.NewInt(notaryParamAlphaLoc), big.NewInt(int64(cfg.NotaryParamAlpha*decimalMultiplier)))
+	s.setStateBigInt(big.NewInt(notaryParamBetaLoc), big.NewInt(int64(cfg.NotaryParamBeta*decimalMultiplier)))
 	s.setStateBigInt(big.NewInt(roundLengthLoc), big.NewInt(int64(cfg.RoundLength)))
 	s.setStateBigInt(big.NewInt(minBlockIntervalLoc), big.NewInt(int64(cfg.MinBlockInterval)))
 	s.SetFineValues(cfg.FineValues)
+
+	// Calculate set size.
+	s.CalNotarySetSize()
+	s.CalDKGSetSize()
 }
 
 type rawConfigStruct struct {
@@ -972,8 +1011,8 @@ type rawConfigStruct struct {
 	MinGasPrice      *big.Int
 	LambdaBA         *big.Int
 	LambdaDKG        *big.Int
-	NotarySetSize    *big.Int
-	DKGSetSize       *big.Int
+	NotaryParamAlpha *big.Int
+	NotaryParamBeta  *big.Int
 	RoundLength      *big.Int
 	MinBlockInterval *big.Int
 	FineValues       []*big.Int
@@ -987,11 +1026,14 @@ func (s *GovernanceState) UpdateConfigurationRaw(cfg *rawConfigStruct) {
 	s.setStateBigInt(big.NewInt(blockGasLimitLoc), cfg.BlockGasLimit)
 	s.setStateBigInt(big.NewInt(lambdaBALoc), cfg.LambdaBA)
 	s.setStateBigInt(big.NewInt(lambdaDKGLoc), cfg.LambdaDKG)
-	s.setStateBigInt(big.NewInt(notarySetSizeLoc), cfg.NotarySetSize)
-	s.setStateBigInt(big.NewInt(dkgSetSizeLoc), cfg.DKGSetSize)
+	s.setStateBigInt(big.NewInt(notaryParamAlphaLoc), cfg.NotaryParamAlpha)
+	s.setStateBigInt(big.NewInt(notaryParamBetaLoc), cfg.NotaryParamBeta)
 	s.setStateBigInt(big.NewInt(roundLengthLoc), cfg.RoundLength)
 	s.setStateBigInt(big.NewInt(minBlockIntervalLoc), cfg.MinBlockInterval)
 	s.SetFineValues(cfg.FineValues)
+
+	s.CalNotarySetSize()
+	s.CalDKGSetSize()
 }
 
 // event ConfigurationChanged();
@@ -1488,6 +1530,7 @@ func (g *GovernanceContract) updateConfiguration(cfg *rawConfigStruct) ([]byte,
 
 	g.state.UpdateConfigurationRaw(cfg)
 	g.state.emitConfigurationChangedEvent()
+
 	return nil, nil
 }
 
@@ -1530,6 +1573,9 @@ func (g *GovernanceContract) register(
 	if value.Cmp(big.NewInt(0)) > 0 {
 		g.state.IncTotalStaked(value)
 		g.state.emitStaked(caller, value)
+
+		g.state.CalNotarySetSize()
+		g.state.CalDKGSetSize()
 	}
 	return g.useGas(GovernanceActionGasCost)
 }
@@ -1557,6 +1603,10 @@ func (g *GovernanceContract) stake() ([]byte, error) {
 
 	g.state.IncTotalStaked(value)
 	g.state.emitStaked(caller, value)
+
+	g.state.CalNotarySetSize()
+	g.state.CalDKGSetSize()
+
 	return g.useGas(GovernanceActionGasCost)
 }
 
@@ -1591,6 +1641,9 @@ func (g *GovernanceContract) unstake(amount *big.Int) ([]byte, error) {
 	g.state.DecTotalStaked(amount)
 	g.state.emitUnstaked(caller, amount)
 
+	g.state.CalNotarySetSize()
+	g.state.CalDKGSetSize()
+
 	return g.useGas(GovernanceActionGasCost)
 }
 
diff --git a/core/vm/oracle_contracts_test.go b/core/vm/oracle_contracts_test.go
index 868ea533c..69e13e1a1 100644
--- a/core/vm/oracle_contracts_test.go
+++ b/core/vm/oracle_contracts_test.go
@@ -492,8 +492,8 @@ func (g *OracleContractsTestSuite) TestUpdateConfiguration() {
 		big.NewInt(8000000),
 		big.NewInt(250),
 		big.NewInt(2500),
-		big.NewInt(4),
-		big.NewInt(4),
+		big.NewInt(int64(70.5*decimalMultiplier)),
+		big.NewInt(264*decimalMultiplier),
 		big.NewInt(600),
 		big.NewInt(900),
 		[]*big.Int{big.NewInt(1), big.NewInt(1), big.NewInt(1)})
@@ -591,7 +591,7 @@ func (g *OracleContractsTestSuite) TestConfigurationReading() {
 	g.Require().NoError(err)
 	err = GovernanceABI.ABI.Unpack(&value, "notarySetSize", res)
 	g.Require().NoError(err)
-	g.Require().Equal(g.config.NotarySetSize, uint32(value.Uint64()))
+	g.Require().True(uint32(value.Uint64()) > 0)
 
 	// DKGRound.
 	input, err = GovernanceABI.ABI.Pack("dkgRound")
@@ -612,7 +612,7 @@ func (g *OracleContractsTestSuite) TestConfigurationReading() {
 	g.Require().NoError(err)
 	err = GovernanceABI.ABI.Unpack(&value, "dkgSetSize", res)
 	g.Require().NoError(err)
-	g.Require().Equal(g.config.DKGSetSize, uint32(value.Uint64()))
+	g.Require().True(uint32(value.Uint64()) > 0)
 
 	// RoundLength.
 	input, err = GovernanceABI.ABI.Pack("roundLength")
diff --git a/params/config.go b/params/config.go
index 52570d5a4..f61a9b6df 100644
--- a/params/config.go
+++ b/params/config.go
@@ -26,10 +26,10 @@ import (
 
 // Genesis hashes to enforce below configs on.
 var (
-	MainnetGenesisHash = common.HexToHash("0xcde2f22a8ccad92a6839880e445bccf3949aae712056a9d139a318f9f4b18fe8")
-	TestnetGenesisHash = common.HexToHash("0x7463c980be61ae7e32e8a7611c9532989dfc4463c264b9ef3d31bfe490780425")
-	TaipeiGenesisHash  = common.HexToHash("0x953540c8dc6155c506b85be9944b97c636948e2cb47b698e4bdf7d58563a6e01")
-	YilanGenesisHash   = common.HexToHash("0x70654e2b863f01f00f843e6c4b0ecf2af39f7e27493f577ca4526b40eb1773c7")
+	MainnetGenesisHash = common.HexToHash("0x8ac8e240790046eb72225eb2a2381f3ef5a7a88291fffc702ba08503cc2a1341")
+	TestnetGenesisHash = common.HexToHash("0x3caf9a977e579b4de001956508b57563a4b61742c66f49323a1294ad214da29d")
+	TaipeiGenesisHash  = common.HexToHash("0x13e85a0207f2888ac9c1746c94d5d7fd87ff637cbd080b42d5db1252341f4428")
+	YilanGenesisHash   = common.HexToHash("0x6b1a94b5e4c24665942a3b768bd98b39d61771a5eaba97c0466644d78d8a2f11")
 )
 
 // TrustedCheckpoints associates each known checkpoint with the genesis hash of
@@ -66,8 +66,8 @@ var (
 			BlockGasLimit:     40000000,
 			LambdaBA:          250,
 			LambdaDKG:         2500,
-			NotarySetSize:     4,
-			DKGSetSize:        4,
+			NotaryParamAlpha:  70.5,
+			NotaryParamBeta:   264,
 			RoundLength:       600,
 			MinBlockInterval:  1000,
 			FineValues: []*big.Int{
@@ -117,8 +117,8 @@ var (
 			BlockGasLimit:     80000000,
 			LambdaBA:          250,
 			LambdaDKG:         10000,
-			NotarySetSize:     24,
-			DKGSetSize:        24,
+			NotaryParamAlpha:  70.5,
+			NotaryParamBeta:   264,
 			RoundLength:       1200,
 			MinBlockInterval:  1000,
 			FineValues: []*big.Int{
@@ -159,8 +159,8 @@ var (
 			BlockGasLimit:     21000 * 5000,
 			LambdaBA:          250,
 			LambdaDKG:         10000,
-			NotarySetSize:     24,
-			DKGSetSize:        24,
+			NotaryParamAlpha:  70.5,
+			NotaryParamBeta:   264,
 			RoundLength:       1200,
 			MinBlockInterval:  500,
 			FineValues: []*big.Int{
@@ -209,8 +209,8 @@ var (
 			BlockGasLimit:     21000 * 5000,
 			LambdaBA:          250,
 			LambdaDKG:         10000,
-			NotarySetSize:     4,
-			DKGSetSize:        4,
+			NotaryParamAlpha:  70.5,
+			NotaryParamBeta:   264,
 			RoundLength:       1200,
 			MinBlockInterval:  500,
 			FineValues: []*big.Int{
@@ -359,8 +359,8 @@ type DexconConfig struct {
 	BlockGasLimit     uint64         `json:"blockGasLimit"`
 	LambdaBA          uint64         `json:"lambdaBA"`
 	LambdaDKG         uint64         `json:"lambdaDKG"`
-	NotarySetSize     uint32         `json:"notarySetSize"`
-	DKGSetSize        uint32         `json:"dkgSetSize"`
+	NotaryParamAlpha  float32        `json:"notaryParamAlpha"`
+	NotaryParamBeta   float32        `json:"notaryParamBeta"`
 	RoundLength       uint64         `json:"roundLength"`
 	MinBlockInterval  uint64         `json:"minBlockInterval"`
 	FineValues        []*big.Int     `json:"fineValues"`
@@ -376,7 +376,7 @@ type dexconConfigSpecMarshaling struct {
 
 // String implements the stringer interface, returning the consensus engine details.
 func (d *DexconConfig) String() string {
-	return fmt.Sprintf("{GenesisCRSText: %v Owner: %v MinStake: %v LockupPeriod: %v MiningVelocity: %v NextHalvingSupply: %v LastHalvedAmount: %v MinGasPrice: %v BlockGasLimit: %v LambdaBA: %v LambdaDKG: %v NotarySetSize: %v DKGSetSize: %v RoundLength: %v MinBlockInterval: %v FineValues: %v}",
+	return fmt.Sprintf("{GenesisCRSText: %v Owner: %v MinStake: %v LockupPeriod: %v MiningVelocity: %v NextHalvingSupply: %v LastHalvedAmount: %v MinGasPrice: %v BlockGasLimit: %v LambdaBA: %v LambdaDKG: %v NotaryParamAlpha: %v NotaryParamBeta: %v RoundLength: %v MinBlockInterval: %v FineValues: %v}",
 		d.GenesisCRSText,
 		d.Owner,
 		d.MinStake,
@@ -388,8 +388,8 @@ func (d *DexconConfig) String() string {
 		d.BlockGasLimit,
 		d.LambdaBA,
 		d.LambdaDKG,
-		d.NotarySetSize,
-		d.DKGSetSize,
+		d.NotaryParamAlpha,
+		d.NotaryParamBeta,
 		d.RoundLength,
 		d.MinBlockInterval,
 		d.FineValues,
diff --git a/params/gen_dexcon_config.go b/params/gen_dexcon_config.go
index 38753916a..dbceb1676 100644
--- a/params/gen_dexcon_config.go
+++ b/params/gen_dexcon_config.go
@@ -26,8 +26,8 @@ func (d DexconConfig) MarshalJSON() ([]byte, error) {
 		BlockGasLimit     uint64                  `json:"blockGasLimit"`
 		LambdaBA          uint64                  `json:"lambdaBA"`
 		LambdaDKG         uint64                  `json:"lambdaDKG"`
-		NotarySetSize     uint32                  `json:"notarySetSize"`
-		DKGSetSize        uint32                  `json:"dkgSetSize"`
+		NotaryParamAlpha  float32                 `json:"notaryParamAlpha"`
+		NotaryParamBeta   float32                 `json:"notaryParamBeta"`
 		RoundLength       uint64                  `json:"roundLength"`
 		MinBlockInterval  uint64                  `json:"minBlockInterval"`
 		FineValues        []*math.HexOrDecimal256 `json:"fineValues"`
@@ -44,8 +44,8 @@ func (d DexconConfig) MarshalJSON() ([]byte, error) {
 	enc.BlockGasLimit = d.BlockGasLimit
 	enc.LambdaBA = d.LambdaBA
 	enc.LambdaDKG = d.LambdaDKG
-	enc.NotarySetSize = d.NotarySetSize
-	enc.DKGSetSize = d.DKGSetSize
+	enc.NotaryParamAlpha = d.NotaryParamAlpha
+	enc.NotaryParamBeta = d.NotaryParamBeta
 	enc.RoundLength = d.RoundLength
 	enc.MinBlockInterval = d.MinBlockInterval
 	if d.FineValues != nil {
@@ -71,8 +71,8 @@ func (d *DexconConfig) UnmarshalJSON(input []byte) error {
 		BlockGasLimit     *uint64                 `json:"blockGasLimit"`
 		LambdaBA          *uint64                 `json:"lambdaBA"`
 		LambdaDKG         *uint64                 `json:"lambdaDKG"`
-		NotarySetSize     *uint32                 `json:"notarySetSize"`
-		DKGSetSize        *uint32                 `json:"dkgSetSize"`
+		NotaryParamAlpha  *float32                `json:"notaryParamAlpha"`
+		NotaryParamBeta   *float32                `json:"notaryParamBeta"`
 		RoundLength       *uint64                 `json:"roundLength"`
 		MinBlockInterval  *uint64                 `json:"minBlockInterval"`
 		FineValues        []*math.HexOrDecimal256 `json:"fineValues"`
@@ -114,11 +114,11 @@ func (d *DexconConfig) UnmarshalJSON(input []byte) error {
 	if dec.LambdaDKG != nil {
 		d.LambdaDKG = *dec.LambdaDKG
 	}
-	if dec.NotarySetSize != nil {
-		d.NotarySetSize = *dec.NotarySetSize
+	if dec.NotaryParamAlpha != nil {
+		d.NotaryParamAlpha = *dec.NotaryParamAlpha
 	}
-	if dec.DKGSetSize != nil {
-		d.DKGSetSize = *dec.DKGSetSize
+	if dec.NotaryParamBeta != nil {
+		d.NotaryParamBeta = *dec.NotaryParamBeta
 	}
 	if dec.RoundLength != nil {
 		d.RoundLength = *dec.RoundLength
diff --git a/test/genesis.json b/test/genesis.json
index 8be5a844d..5a2891dcd 100644
--- a/test/genesis.json
+++ b/test/genesis.json
@@ -23,8 +23,8 @@
       "blockGasLimit": 40000000,
       "lambdaBA": 250,
       "lambdaDKG": 1500,
-      "notarySetSize": 4,
-      "dkgSetSize": 4,
+      "notaryParamAlpha": 70.5,
+      "notaryParamBeta": 264,
       "roundLength": 100,
       "minBlockInterval": 500,
       "fineValues": [