feat: recommit bid when newBidCh is empty to maximize mev reward (#2424)

bnb-chain · Apr 28, 2024 · ba67263 · ba67263
1 parent 6573254
commit ba67263
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Showing 2 changed files with 52 additions and 24 deletions.
diff --git a/miner/bid_simulator.go b/miner/bid_simulator.go
@@ -30,8 +30,6 @@ const (
 	// maxBidPerBuilderPerBlock is the max bid number per builder
 	maxBidPerBuilderPerBlock = 3
 
-	commitInterruptBetterBid = 1
-
 	// leftOverTimeRate is the rate of left over time to simulate a bid
 	leftOverTimeRate = 11
 	// leftOverTimeScale is the scale of left over time to simulate a bid
@@ -311,16 +309,15 @@ func (b *bidSimulator) newBidLoop() {
 
 	// commit aborts in-flight bid execution with given signal and resubmits a new one.
 	commit := func(reason int32, bidRuntime *BidRuntime) {
-		log.Debug("BidSimulator: start", "bidHash", bidRuntime.bid.Hash().Hex())
-
 		// if the left time is not enough to do simulation, return
 		var simDuration time.Duration
 		if lastBid := b.GetBestBid(bidRuntime.bid.ParentHash); lastBid != nil && lastBid.duration != 0 {
 			simDuration = lastBid.duration
 		}
 
 		if time.Until(b.bidMustBefore(bidRuntime.bid.ParentHash)) <= simDuration*leftOverTimeRate/leftOverTimeScale {
-			log.Debug("BidSimulator: abort commit, not enough time to simulate", "bidHash", bidRuntime.bid.Hash().Hex())
+			log.Debug("BidSimulator: abort commit, not enough time to simulate",
+				"builder", bidRuntime.bid.Builder, "bidHash", bidRuntime.bid.Hash().Hex())
 			return
 		}
 
@@ -332,6 +329,7 @@ func (b *bidSimulator) newBidLoop() {
 		interruptCh = make(chan int32, 1)
 		select {
 		case b.simBidCh <- &simBidReq{interruptCh: interruptCh, bid: bidRuntime}:
+			log.Debug("BidSimulator: commit", "builder", bidRuntime.bid.Builder, "bidHash", bidRuntime.bid.Hash().Hex())
 		case <-b.exitCh:
 			return
 		}
@@ -352,7 +350,8 @@ func (b *bidSimulator) newBidLoop() {
 
 			if expectedValidatorReward.Cmp(big.NewInt(0)) < 0 {
 				// damage self profit, ignore
-				log.Debug("BidSimulator: invalid bid, validator reward is less than 0, ignore", "bidHash", newBid.Hash().Hex())
+				log.Debug("BidSimulator: invalid bid, validator reward is less than 0, ignore",
+					"builder", newBid.Builder, "bidHash", newBid.Hash().Hex())
 				continue
 			}
 
@@ -375,26 +374,27 @@ func (b *bidSimulator) newBidLoop() {
 				}
 
 				// if bestBid is not nil, check if newBid is better than bestBid
-				if bidRuntime.expectedBlockReward.Cmp(bestBid.expectedBlockReward) > 0 &&
-					bidRuntime.expectedValidatorReward.Cmp(bestBid.expectedValidatorReward) > 0 {
+				if bidRuntime.expectedBlockReward.Cmp(bestBid.expectedBlockReward) >= 0 &&
+					bidRuntime.expectedValidatorReward.Cmp(bestBid.expectedValidatorReward) >= 0 {
 					// if both reward are better than last simulating newBid, commit for simulation
 					commit(commitInterruptBetterBid, bidRuntime)
 					continue
 				}
 
-				log.Debug("BidSimulator: lower reward, ignore", "bidHash", newBid.Hash().Hex())
+				log.Debug("BidSimulator: lower reward, ignore",
+					"builder", bidRuntime.bid.Builder, "bidHash", newBid.Hash().Hex())
 				continue
 			}
 
 			// simulatingBid must be better than bestBid, if newBid is better than simulatingBid, commit for simulation
-			if bidRuntime.expectedBlockReward.Cmp(simulatingBid.expectedBlockReward) > 0 &&
-				bidRuntime.expectedValidatorReward.Cmp(simulatingBid.expectedValidatorReward) > 0 {
+			if bidRuntime.expectedBlockReward.Cmp(simulatingBid.expectedBlockReward) >= 0 &&
+				bidRuntime.expectedValidatorReward.Cmp(simulatingBid.expectedValidatorReward) >= 0 {
 				// if both reward are better than last simulating newBid, commit for simulation
 				commit(commitInterruptBetterBid, bidRuntime)
 				continue
 			}
 
-			log.Debug("BidSimulator: lower reward, ignore", "bidHash", newBid.Hash().Hex())
+			log.Debug("BidSimulator: lower reward, ignore", "builder", newBid.Builder, "bidHash", newBid.Hash().Hex())
 		case <-b.exitCh:
 			return
 		}
@@ -546,12 +546,23 @@ func (b *bidSimulator) simBid(interruptCh chan int32, bidRuntime *BidRuntime) {
 			go b.reportIssue(bidRuntime, err)
 		}
 
+		b.RemoveSimulatingBid(parentHash)
+		bidSimTimer.UpdateSince(start)
+
 		if success {
 			bidRuntime.duration = time.Since(simStart)
-		}
 
-		b.RemoveSimulatingBid(parentHash)
-		bidSimTimer.UpdateSince(start)
+			// only recommit self bid when newBidCh is empty
+			if len(b.newBidCh) > 0 {
+				return
+			}
+
+			select {
+			case b.newBidCh <- bidRuntime.bid:
+				log.Debug("BidSimulator: recommit", "builder", bidRuntime.bid.Builder, "bidHash", bidRuntime.bid.Hash().Hex())
+			default:
+			}
+		}
 	}(time.Now())
 
 	// prepareWork will configure header with a suitable time according to consensus
@@ -612,7 +623,8 @@ func (b *bidSimulator) simBid(interruptCh chan int32, bidRuntime *BidRuntime) {
 	if b.config.GreedyMergeTx {
 		delay := b.engine.Delay(b.chain, bidRuntime.env.header, &b.delayLeftOver)
 		if delay != nil && *delay > 0 {
-			log.Debug("BidSimulator: greedy merge tx stopTimer", "block", bidRuntime.env.header.Number,
+			log.Debug("BidSimulator: greedy merge stopTimer", "block", bidRuntime.env.header.Number,
+				"builder", bidRuntime.bid.Builder,
 				"header time", time.Until(time.Unix(int64(bidRuntime.env.header.Time), 0)),
 				"commit delay", *delay, "DelayLeftOver", b.delayLeftOver)
 
@@ -624,8 +636,8 @@ func (b *bidSimulator) simBid(interruptCh chan int32, bidRuntime *BidRuntime) {
 			}
 
 			fillErr := b.bidWorker.fillTransactions(interruptCh, bidRuntime.env, stopTimer, bidTxsSet)
-			log.Info("BidSimulator: greedy merge tx fill transactions", "block", bidRuntime.env.header.Number,
-				"tx count", bidRuntime.env.tcount-bidTxLen+1, "err", fillErr)
+			log.Info("BidSimulator: greedy merge stopped", "block", bidRuntime.env.header.Number,
+				"builder", bidRuntime.bid.Builder, "tx count", bidRuntime.env.tcount-bidTxLen+1, "err", fillErr)
 
 			// recalculate the packed reward
 			bidRuntime.packReward(b.config.ValidatorCommission)
@@ -635,7 +647,8 @@ func (b *bidSimulator) simBid(interruptCh chan int32, bidRuntime *BidRuntime) {
 	bidRuntime.env.gasPool.AddGas(params.PayBidTxGasLimit)
 	err = bidRuntime.commitTransaction(b.chain, b.chainConfig, payBidTx)
 	if err != nil {
-		log.Error("BidSimulator: failed to commit tx", "bidHash", bidRuntime.bid.Hash(), "tx", payBidTx.Hash(), "err", err)
+		log.Error("BidSimulator: failed to commit tx", "builder", bidRuntime.bid.Builder,
+			"bidHash", bidRuntime.bid.Hash(), "tx", payBidTx.Hash(), "err", err)
 		err = fmt.Errorf("invalid tx in bid, %v", err)
 		return
 	}
@@ -649,11 +662,22 @@ func (b *bidSimulator) simBid(interruptCh chan int32, bidRuntime *BidRuntime) {
 	}
 
 	// this is the simplest strategy: best for all the delegators.
-	if bidRuntime.packedBlockReward.Cmp(bestBid.packedBlockReward) > 0 {
+	if bidRuntime.packedBlockReward.Cmp(bestBid.packedBlockReward) >= 0 {
 		b.SetBestBid(bidRuntime.bid.ParentHash, bidRuntime)
 		success = true
 		return
 	}
+
+	// only recommit last best bid when newBidCh is empty
+	if len(b.newBidCh) > 0 {
+		return
+	}
+
+	select {
+	case b.newBidCh <- bestBid.bid:
+		log.Debug("BidSimulator: recommit last bid", "builder", bidRuntime.bid.Builder, "bidHash", bidRuntime.bid.Hash().Hex())
+	default:
+	}
 }
 
 // reportIssue reports the issue to the mev-sentry

diff --git a/miner/worker.go b/miner/worker.go
@@ -73,10 +73,11 @@ var (
 	writeBlockTimer    = metrics.NewRegisteredTimer("worker/writeblock", nil)
 	finalizeBlockTimer = metrics.NewRegisteredTimer("worker/finalizeblock", nil)
 
-	errBlockInterruptedByNewHead  = errors.New("new head arrived while building block")
-	errBlockInterruptedByRecommit = errors.New("recommit interrupt while building block")
-	errBlockInterruptedByTimeout  = errors.New("timeout while building block")
-	errBlockInterruptedByOutOfGas = errors.New("out of gas while building block")
+	errBlockInterruptedByNewHead   = errors.New("new head arrived while building block")
+	errBlockInterruptedByRecommit  = errors.New("recommit interrupt while building block")
+	errBlockInterruptedByTimeout   = errors.New("timeout while building block")
+	errBlockInterruptedByOutOfGas  = errors.New("out of gas while building block")
+	errBlockInterruptedByBetterBid = errors.New("better bid arrived while building block")
 )
 
 // environment is the worker's current environment and holds all
@@ -145,6 +146,7 @@ const (
 	commitInterruptResubmit
 	commitInterruptTimeout
 	commitInterruptOutOfGas
+	commitInterruptBetterBid
 )
 
 // newWorkReq represents a request for new sealing work submitting with relative interrupt notifier.
@@ -1481,6 +1483,8 @@ func signalToErr(signal int32) error {
 		return errBlockInterruptedByTimeout
 	case commitInterruptOutOfGas:
 		return errBlockInterruptedByOutOfGas
+	case commitInterruptBetterBid:
+		return errBlockInterruptedByBetterBid
 	default:
 		panic(fmt.Errorf("undefined signal %d", signal))
 	}