From f485534846aef73f08c5fdaffac9918f1bc33bdb Mon Sep 17 00:00:00 2001 From: Boris Nagaev Date: Fri, 28 Jun 2024 21:34:55 -0300 Subject: [PATCH] sweepbatcher: add greedy batch selection algorithm If custom fee rates are used, the algorithm is tried. It selects a batch for the sweep using the greedy algorithm, which minimizes costs, and adds the sweep to the batch. If it fails, old algorithm is used, trying to add to any batch, or starting a new batch. --- sweepbatcher/greedy_batch_selection.go | 306 +++++++++ sweepbatcher/greedy_batch_selection_test.go | 684 ++++++++++++++++++++ sweepbatcher/sweep_batch.go | 6 + sweepbatcher/sweep_batcher.go | 25 + 4 files changed, 1021 insertions(+) create mode 100644 sweepbatcher/greedy_batch_selection.go create mode 100644 sweepbatcher/greedy_batch_selection_test.go diff --git a/sweepbatcher/greedy_batch_selection.go b/sweepbatcher/greedy_batch_selection.go new file mode 100644 index 000000000..6696d6583 --- /dev/null +++ b/sweepbatcher/greedy_batch_selection.go @@ -0,0 +1,306 @@ +package sweepbatcher + +import ( + "context" + "errors" + "fmt" + + "github.com/btcsuite/btcd/btcutil" + "github.com/btcsuite/btcd/txscript" + sweeppkg "github.com/lightninglabs/loop/sweep" + "github.com/lightningnetwork/lnd/input" + "github.com/lightningnetwork/lnd/lntypes" + "github.com/lightningnetwork/lnd/lnwallet/chainfee" +) + +// greedyAddSweep selects a batch for the sweep using the greedy algorithm, +// which minimizes costs, and adds the sweep to the batch. To accomplish this, +// it first collects fee details about the sweep being added, about a potential +// new batch composed of this sweep only, and about all existing batches. Then +// it passes the data to selectBatch() function, which emulates adding the sweep +// to each batch and creating new batch for the sweep, and calculates the costs +// of each alternative. Based on the estimates of selectBatch(), this method +// adds the sweep to a batch, or creates new batch for it. If this method fails +// for whatever reason, the caller falls back to the simple algorithm (method +// handleSweep). +func (b *Batcher) greedyAddSweep(ctx context.Context, sweep *sweep) error { + if b.customFeeRate == nil { + return errors.New("greedy batch selection algorithm requires " + + "setting custom fee rate provider") + } + + // Collect weight and fee rate info about the sweep and new batch. + sweepFeeDetails, newBatchFeeDetails, err := estimateSweepFeeIncrement( + sweep, + ) + if err != nil { + return fmt.Errorf("failed to estimate tx weight for "+ + "sweep %x: %w", sweep.swapHash[:6], err) + } + + // Collect weight and fee rate info about existing batches. + batches := make([]feeDetails, 0, len(b.batches)) + for _, batch := range b.batches { + newBatchFeeDetails, err := estimateBatchWeight(batch) + if err != nil { + return fmt.Errorf("failed to estimate tx weight for "+ + "batch %d: %w", batch.id, err) + } + batches = append(batches, newBatchFeeDetails) + } + + // Run the algorithm. Get batchId of the best batch, or specialId if the + // best option is to create new batch. + batchId, err := selectBatch( + batches, sweepFeeDetails, newBatchFeeDetails, + ) + if err != nil { + return fmt.Errorf("batch selection algorithm failed for sweep "+ + "%x: %w", sweep.swapHash[:6], err) + } + + // If the best option is to start new batch, do it. + if batchId == specialId { + return b.launchNewBatch(ctx, sweep) + } + + // Locate the batch to add the sweep to. + batch, has := b.batches[batchId] + if !has { + return fmt.Errorf("batch selection algorithm returned "+ + "batch id %d which doesn't exist, for sweep %x", + batchId, sweep.swapHash[:6]) + } + + // Add the sweep to the batch. + accepted, err := batch.addSweep(ctx, sweep) + if err != nil { + return fmt.Errorf("batch selection algorithm returned "+ + "batch id %d for sweep %x, but adding failed: %w", + batchId, sweep.swapHash[:6], err) + } + if !accepted { + return fmt.Errorf("batch selection algorithm returned "+ + "batch id %d for sweep %x, but acceptance failed", + batchId, sweep.swapHash[:6]) + } + + return nil +} + +// estimateSweepFeeIncrement returns fee details for adding the sweep to a batch +// and for creating new batch with this sweep only. +func estimateSweepFeeIncrement(s *sweep) (feeDetails, feeDetails, error) { + // Create a fake batch with this sweep. + batch := &batch{ + rbfCache: rbfCache{ + FeeRate: s.minFeeRate, + }, + sweeps: map[lntypes.Hash]sweep{ + s.swapHash: *s, + }, + } + + // Estimate new batch. + newBatch, err := estimateBatchWeight(batch) + if err != nil { + return feeDetails{}, feeDetails{}, err + } + + // Add the same sweep again to measure weight increments. + swapHash2 := s.swapHash + swapHash2[0]++ + batch.sweeps[swapHash2] = *s + + // Estimate weight of a batch with two sweeps. + batch2, err := estimateBatchWeight(batch) + if err != nil { + return feeDetails{}, feeDetails{}, err + } + + // Create feeDetails for sweep. + sweepFeeDetails := feeDetails{ + FeeRate: s.minFeeRate, + NonCoopHint: s.nonCoopHint, + IsExternalAddr: s.isExternalAddr, + + // Calculate sweep weight as a difference. + CoopWeight: batch2.CoopWeight - newBatch.CoopWeight, + NonCoopWeight: batch2.NonCoopWeight - newBatch.NonCoopWeight, + } + + return sweepFeeDetails, newBatch, nil +} + +// estimateBatchWeight estimates batch weight and returns its fee details. +func estimateBatchWeight(batch *batch) (feeDetails, error) { + // Make sure the batch is not empty. + if len(batch.sweeps) == 0 { + return feeDetails{}, errors.New("empty batch") + } + + // Make sure fee rate is valid. + if batch.rbfCache.FeeRate < chainfee.AbsoluteFeePerKwFloor { + return feeDetails{}, fmt.Errorf("feeRate is too low: %v", + batch.rbfCache.FeeRate) + } + + // Find if the batch has at least one non-cooperative sweep. + hasNonCoop := false + for _, sweep := range batch.sweeps { + if sweep.nonCoopHint { + hasNonCoop = true + } + } + + // Find some sweep of the batch. It is used if there is just one sweep. + var theSweep sweep + for _, sweep := range batch.sweeps { + theSweep = sweep + break + } + + // Find sweep destination address (type) for weight estimations. + var destAddr btcutil.Address + if theSweep.isExternalAddr { + if theSweep.destAddr == nil { + return feeDetails{}, errors.New("isExternalAddr=true, " + + "but destAddr is nil") + } + destAddr = theSweep.destAddr + } else { + // Assume it is taproot by default. + destAddr = (*btcutil.AddressTaproot)(nil) + } + + // Make two estimators: for coop and non-coop cases. + var coopWeight, nonCoopWeight input.TxWeightEstimator + + // Add output weight to the estimator. + err := sweeppkg.AddOutputEstimate(&coopWeight, destAddr) + if err != nil { + return feeDetails{}, fmt.Errorf("sweep.AddOutputEstimate: %w", + err) + } + err = sweeppkg.AddOutputEstimate(&nonCoopWeight, destAddr) + if err != nil { + return feeDetails{}, fmt.Errorf("sweep.AddOutputEstimate: %w", + err) + } + + // Add inputs. + for _, sweep := range batch.sweeps { + // TODO: it should be txscript.SigHashDefault. + coopWeight.AddTaprootKeySpendInput(txscript.SigHashAll) + + err = sweep.htlcSuccessEstimator(&nonCoopWeight) + if err != nil { + return feeDetails{}, fmt.Errorf("htlcSuccessEstimator "+ + "failed: %w", err) + } + } + + return feeDetails{ + BatchId: batch.id, + FeeRate: batch.rbfCache.FeeRate, + CoopWeight: coopWeight.Weight(), + NonCoopWeight: nonCoopWeight.Weight(), + NonCoopHint: hasNonCoop, + IsExternalAddr: theSweep.isExternalAddr, + }, nil +} + +// specialId is the value that indicates a new batch. It is returned by +// selectBatch if the most cost-efficient action is new batch creation. +const specialId = -1 + +// feeDetails is either a batch or a sweep and it holds data important for +// selection of a batch to add the sweep to (or new batch creation). +type feeDetails struct { + BatchId int32 + FeeRate chainfee.SatPerKWeight + CoopWeight lntypes.WeightUnit + NonCoopWeight lntypes.WeightUnit + NonCoopHint bool + IsExternalAddr bool +} + +// fee returns fee of onchain transaction representing this instance. +func (e feeDetails) fee() btcutil.Amount { + var weight lntypes.WeightUnit + if e.NonCoopHint { + weight = e.NonCoopWeight + } else { + weight = e.CoopWeight + } + + return e.FeeRate.FeeForWeight(weight) +} + +// combine returns new feeDetails, combining properties. +func (e1 feeDetails) combine(e2 feeDetails) feeDetails { + // The fee rate is max of two fee rates. + feeRate := e1.FeeRate + if feeRate < e2.FeeRate { + feeRate = e2.FeeRate + } + + return feeDetails{ + FeeRate: feeRate, + CoopWeight: e1.CoopWeight + e2.CoopWeight, + NonCoopWeight: e1.NonCoopWeight + e2.NonCoopWeight, + NonCoopHint: e1.NonCoopHint || e2.NonCoopHint, + IsExternalAddr: e1.IsExternalAddr || e2.IsExternalAddr, + } +} + +// selectBatch returns index of the batch adding to which minimizes costs. +// For each batch its fee rate and two weight are provided: weight in case of +// cooperative spending and weight in case non-cooperative spending (using +// preimages instead of taproot key spend). Also a hint is provided to signal +// if the batch has to use non-cooperative spending path. The same data is also +// provided to the sweep for which we are selecting a batch to add. In case of +// the sweep weights are weight deltas resulted from adding the sweep. Finally, +// the same data is provided for new batch having this sweep only. The algorithm +// compares costs of adding the sweep to each existing batch, and costs of new +// batch creation for this sweep and returns BatchId of the winning batch. If +// the best option is to create a new batch, it returns specialId. Each fee +// details has also IsExternalAddr flag. There is a rule that sweeps having flag +// IsExternalAddr must go in individual batches. Cooperative spending is only +// available if all the sweeps support cooperative spending path. +func selectBatch(batches []feeDetails, sweep, oneSweepBatch feeDetails) (int32, error) { + // Track the best batch to add a sweep to. The default case is new batch + // creation with this sweep only in it. The cost is its full fee. + bestBatchId := int32(specialId) + bestCost := oneSweepBatch.fee() + + // Try to add the sweep to every batch, calculate the costs and + // find the batch adding to which results in minimum costs. + for _, batch := range batches { + // If either the batch or the sweep has IsExternalAddr flag, + // the sweep can't be added to the batch, so skip. + if batch.IsExternalAddr || sweep.IsExternalAddr { + continue + } + + // Add the sweep to the batch virtually. + combinedBatch := batch.combine(sweep) + + // The cost is fee increase. + cost := combinedBatch.fee() - batch.fee() + + // The cost must be positive, because we added a sweep. + if cost <= 0 { + return 0, fmt.Errorf("got non-positive cost of adding "+ + "sweep to batch %d: %d", batch.BatchId, cost) + } + + // Track the best batch, according to the costs. + if bestCost > cost { + bestBatchId = batch.BatchId + bestCost = cost + } + } + + return bestBatchId, nil +} diff --git a/sweepbatcher/greedy_batch_selection_test.go b/sweepbatcher/greedy_batch_selection_test.go new file mode 100644 index 000000000..8752358e0 --- /dev/null +++ b/sweepbatcher/greedy_batch_selection_test.go @@ -0,0 +1,684 @@ +package sweepbatcher + +import ( + "testing" + + "github.com/btcsuite/btcd/btcutil" + "github.com/btcsuite/btcd/chaincfg" + "github.com/lightninglabs/loop/swap" + "github.com/lightningnetwork/lnd/input" + "github.com/lightningnetwork/lnd/lntypes" + "github.com/lightningnetwork/lnd/lnwallet/chainfee" + "github.com/stretchr/testify/require" +) + +// Useful constants for tests. +const ( + lowFeeRate = chainfee.FeePerKwFloor + highFeeRate = chainfee.SatPerKWeight(30000) + + coopInputWeight = lntypes.WeightUnit(231) + nonCoopInputWeight = lntypes.WeightUnit(521) + nonCoopPenalty = nonCoopInputWeight - coopInputWeight + coopNewBatchWeight = lntypes.WeightUnit(396) + nonCoopNewBatchWeight = coopNewBatchWeight + nonCoopPenalty +) + +// testHtlcV2SuccessEstimator adds weight of non-cooperative input to estimator +// using HTLC v2. +func testHtlcV2SuccessEstimator(estimator *input.TxWeightEstimator) error { + swapHash := lntypes.Hash{1, 1, 1} + htlc, err := swap.NewHtlcV2( + 111, htlcKeys.SenderScriptKey, htlcKeys.ReceiverScriptKey, + swapHash, &chaincfg.RegressionNetParams, + ) + if err != nil { + return err + } + return htlc.AddSuccessToEstimator(estimator) +} + +// testHtlcV3SuccessEstimator adds weight of non-cooperative input to estimator +// using HTLC v3. +func testHtlcV3SuccessEstimator(estimator *input.TxWeightEstimator) error { + swapHash := lntypes.Hash{1, 1, 1} + htlc, err := swap.NewHtlcV3( + input.MuSig2Version100RC2, 111, + htlcKeys.SenderInternalPubKey, htlcKeys.ReceiverInternalPubKey, + htlcKeys.SenderScriptKey, htlcKeys.ReceiverScriptKey, swapHash, + &chaincfg.RegressionNetParams, + ) + if err != nil { + return err + } + return htlc.AddSuccessToEstimator(estimator) +} + +// TestEstimateSweepFeeIncrement tests that weight and fee estimations work +// correctly for a sweep and one sweep batch. +func TestEstimateSweepFeeIncrement(t *testing.T) { + // Useful variables reused in test cases. + se3 := testHtlcV3SuccessEstimator + trAddr := (*btcutil.AddressTaproot)(nil) + p2pkhAddr := (*btcutil.AddressPubKeyHash)(nil) + + cases := []struct { + name string + sweep *sweep + wantSweepFeeDetails feeDetails + wantNewBatchFeeDetails feeDetails + }{ + { + name: "regular", + sweep: &sweep{ + minFeeRate: lowFeeRate, + htlcSuccessEstimator: se3, + }, + wantSweepFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + wantNewBatchFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(445), + NonCoopWeight: lntypes.WeightUnit(735), + }, + }, + + { + name: "high fee rate", + sweep: &sweep{ + minFeeRate: highFeeRate, + htlcSuccessEstimator: se3, + }, + wantSweepFeeDetails: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + wantNewBatchFeeDetails: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: lntypes.WeightUnit(445), + NonCoopWeight: lntypes.WeightUnit(735), + }, + }, + + { + name: "isExternalAddr taproot", + sweep: &sweep{ + minFeeRate: lowFeeRate, + htlcSuccessEstimator: se3, + isExternalAddr: true, + destAddr: trAddr, + }, + wantSweepFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + IsExternalAddr: true, + }, + wantNewBatchFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(445), + NonCoopWeight: lntypes.WeightUnit(735), + IsExternalAddr: true, + }, + }, + + { + name: "isExternalAddr P2PKH", + sweep: &sweep{ + minFeeRate: lowFeeRate, + htlcSuccessEstimator: se3, + isExternalAddr: true, + destAddr: p2pkhAddr, + }, + wantSweepFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + IsExternalAddr: true, + }, + wantNewBatchFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(409), + NonCoopWeight: lntypes.WeightUnit(699), + IsExternalAddr: true, + }, + }, + + { + name: "non-coop", + sweep: &sweep{ + minFeeRate: lowFeeRate, + htlcSuccessEstimator: se3, + nonCoopHint: true, + }, + wantSweepFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + NonCoopHint: true, + }, + wantNewBatchFeeDetails: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(445), + NonCoopWeight: lntypes.WeightUnit(735), + NonCoopHint: true, + }, + }, + } + + for _, tc := range cases { + tc := tc + t.Run(tc.name, func(t *testing.T) { + gotSweepFeeDetails, gotNewBatchFeeDetails, err := + estimateSweepFeeIncrement(tc.sweep) + require.NoError(t, err) + require.Equal( + t, tc.wantSweepFeeDetails, gotSweepFeeDetails, + ) + require.Equal( + t, tc.wantNewBatchFeeDetails, + gotNewBatchFeeDetails, + ) + }) + } +} + +// TestEstimateBatchWeight tests that weight and fee estimations work correctly +// for batches. +func TestEstimateBatchWeight(t *testing.T) { + // Useful variables reused in test cases. + swapHash1 := lntypes.Hash{1, 1, 1} + swapHash2 := lntypes.Hash{2, 2, 2} + se2 := testHtlcV2SuccessEstimator + se3 := testHtlcV3SuccessEstimator + trAddr := (*btcutil.AddressTaproot)(nil) + + cases := []struct { + name string + batch *batch + wantBatchFeeDetails feeDetails + }{ + { + name: "one sweep regular batch", + batch: &batch{ + id: 1, + rbfCache: rbfCache{ + FeeRate: lowFeeRate, + }, + sweeps: map[lntypes.Hash]sweep{ + swapHash1: { + htlcSuccessEstimator: se3, + }, + }, + }, + wantBatchFeeDetails: feeDetails{ + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(445), + NonCoopWeight: lntypes.WeightUnit(735), + }, + }, + + { + name: "two sweeps regular batch", + batch: &batch{ + id: 1, + rbfCache: rbfCache{ + FeeRate: lowFeeRate, + }, + sweeps: map[lntypes.Hash]sweep{ + swapHash1: { + htlcSuccessEstimator: se3, + }, + swapHash2: { + htlcSuccessEstimator: se3, + }, + }, + }, + wantBatchFeeDetails: feeDetails{ + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(676), + NonCoopWeight: lntypes.WeightUnit(1256), + }, + }, + + { + name: "v2 and v3 sweeps", + batch: &batch{ + id: 1, + rbfCache: rbfCache{ + FeeRate: lowFeeRate, + }, + sweeps: map[lntypes.Hash]sweep{ + swapHash1: { + htlcSuccessEstimator: se2, + }, + swapHash2: { + htlcSuccessEstimator: se3, + }, + }, + }, + wantBatchFeeDetails: feeDetails{ + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(676), + NonCoopWeight: lntypes.WeightUnit(1103), + }, + }, + + { + name: "high fee rate", + batch: &batch{ + id: 1, + rbfCache: rbfCache{ + FeeRate: highFeeRate, + }, + sweeps: map[lntypes.Hash]sweep{ + swapHash1: { + htlcSuccessEstimator: se3, + }, + }, + }, + wantBatchFeeDetails: feeDetails{ + BatchId: 1, + FeeRate: highFeeRate, + CoopWeight: lntypes.WeightUnit(445), + NonCoopWeight: lntypes.WeightUnit(735), + }, + }, + + { + name: "non-coop", + batch: &batch{ + id: 1, + rbfCache: rbfCache{ + FeeRate: lowFeeRate, + }, + sweeps: map[lntypes.Hash]sweep{ + swapHash1: { + htlcSuccessEstimator: se3, + }, + swapHash2: { + htlcSuccessEstimator: se3, + nonCoopHint: true, + }, + }, + }, + wantBatchFeeDetails: feeDetails{ + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(676), + NonCoopWeight: lntypes.WeightUnit(1256), + NonCoopHint: true, + }, + }, + + { + name: "isExternalAddr", + batch: &batch{ + id: 1, + rbfCache: rbfCache{ + FeeRate: lowFeeRate, + }, + sweeps: map[lntypes.Hash]sweep{ + swapHash1: { + htlcSuccessEstimator: se3, + isExternalAddr: true, + destAddr: trAddr, + }, + }, + }, + wantBatchFeeDetails: feeDetails{ + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: lntypes.WeightUnit(445), + NonCoopWeight: lntypes.WeightUnit(735), + IsExternalAddr: true, + }, + }, + } + + for _, tc := range cases { + tc := tc + t.Run(tc.name, func(t *testing.T) { + gotBatchFeeDetails, err := estimateBatchWeight(tc.batch) + require.NoError(t, err) + require.Equal( + t, tc.wantBatchFeeDetails, gotBatchFeeDetails, + ) + }) + } +} + +// TestSelectBatch tests greedy batch selection algorithm. +func TestSelectBatch(t *testing.T) { + cases := []struct { + name string + batches []feeDetails + sweep, oneSweepBatch feeDetails + wantBestBatchId int32 + }{ + { + name: "no existing batches", + batches: []feeDetails{}, + sweep: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + oneSweepBatch: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + wantBestBatchId: specialId, + }, + + { + name: "low fee sweep, low fee existing batch", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + oneSweepBatch: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + wantBestBatchId: 1, + }, + + { + name: "low fee sweep, high fee existing batch", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + oneSweepBatch: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + wantBestBatchId: specialId, + }, + + { + name: "low fee sweep, low + high fee existing batches", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + oneSweepBatch: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + wantBestBatchId: 1, + }, + + { + name: "high fee sweep, low + high fee existing batches", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + oneSweepBatch: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + wantBestBatchId: 2, + }, + + { + name: "high fee noncoop sweep", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + NonCoopHint: true, + }, + oneSweepBatch: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + NonCoopHint: true, + }, + wantBestBatchId: specialId, + }, + + { + name: "high fee noncoop sweep, high batch noncoop", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + NonCoopHint: true, + }, + }, + sweep: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + NonCoopHint: true, + }, + oneSweepBatch: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + NonCoopHint: true, + }, + wantBestBatchId: 2, + }, + + { + name: "low fee noncoop sweep", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + NonCoopHint: true, + }, + oneSweepBatch: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + NonCoopHint: true, + }, + wantBestBatchId: specialId, + }, + + { + name: "low fee noncoop sweep, low batch noncoop", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + NonCoopHint: true, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + NonCoopHint: true, + }, + oneSweepBatch: feeDetails{ + FeeRate: lowFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + NonCoopHint: true, + }, + wantBestBatchId: 1, + }, + + { + name: "external address sweep", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + }, + sweep: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + IsExternalAddr: true, + }, + oneSweepBatch: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + IsExternalAddr: true, + }, + wantBestBatchId: specialId, + }, + + { + name: "external address batch", + batches: []feeDetails{ + { + BatchId: 1, + FeeRate: highFeeRate - 1, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + { + BatchId: 2, + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + IsExternalAddr: true, + }, + }, + sweep: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopInputWeight, + NonCoopWeight: nonCoopInputWeight, + }, + oneSweepBatch: feeDetails{ + FeeRate: highFeeRate, + CoopWeight: coopNewBatchWeight, + NonCoopWeight: nonCoopNewBatchWeight, + }, + wantBestBatchId: 1, + }, + } + + for _, tc := range cases { + tc := tc + t.Run(tc.name, func(t *testing.T) { + gotBestBatchId, err := selectBatch( + tc.batches, tc.sweep, tc.oneSweepBatch, + ) + require.NoError(t, err) + require.Equal(t, tc.wantBestBatchId, gotBestBatchId) + }) + } +} diff --git a/sweepbatcher/sweep_batch.go b/sweepbatcher/sweep_batch.go index 47ab5731b..c1d505265 100644 --- a/sweepbatcher/sweep_batch.go +++ b/sweepbatcher/sweep_batch.go @@ -101,6 +101,11 @@ type sweep struct { // minFeeRate is minimum fee rate that must be used by a batch of // the sweep. If it is specified, confTarget is ignored. minFeeRate chainfee.SatPerKWeight + + // nonCoopHint is set, if the sweep can not be spend cooperatively and + // has to be spent using preimage. This is only used in fee estimations + // when selecting a batch for the sweep to minimize fees. + nonCoopHint bool } // batchState is the state of the batch. @@ -838,6 +843,7 @@ func (b *batch) publishBatchCoop(ctx context.Context) (btcutil.Amount, PreviousOutPoint: sweep.outpoint, }) + // TODO: it should be txscript.SigHashDefault. weightEstimate.AddTaprootKeySpendInput(txscript.SigHashAll) } diff --git a/sweepbatcher/sweep_batcher.go b/sweepbatcher/sweep_batcher.go index e72ae1ba8..25599098f 100644 --- a/sweepbatcher/sweep_batcher.go +++ b/sweepbatcher/sweep_batcher.go @@ -121,6 +121,11 @@ type SweepInfo struct { // DestAddr is the destination address of the sweep. DestAddr btcutil.Address + + // NonCoopHint is set, if the sweep can not be spend cooperatively and + // has to be spent using preimage. This is only used in fee estimations + // when selecting a batch for the sweep to minimize fees. + NonCoopHint bool } // SweepFetcher is used to get details of a sweep. @@ -448,6 +453,19 @@ func (b *Batcher) handleSweep(ctx context.Context, sweep *sweep, } } + // If custom fee rate provider is used, run the greedy algorithm of + // batch selection to minimize costs. + if b.customFeeRate != nil { + err := b.greedyAddSweep(ctx, sweep) + if err == nil { + // The greedy algorithm succeeded. + return nil + } + + log.Warnf("Greedy batch selection algorithm failed for sweep "+ + "%x, falling back to old approach.", sweep.swapHash[:6]) + } + // If one of the batches accepts the sweep, we provide it to that batch. for _, batch := range b.batches { accepted, err := batch.addSweep(ctx, sweep) @@ -464,6 +482,12 @@ func (b *Batcher) handleSweep(ctx context.Context, sweep *sweep, // If no batch is capable of accepting the sweep, we spin up a fresh // batch and hand the sweep over to it. + return b.launchNewBatch(ctx, sweep) +} + +// launchNewBatch creates new batch, starts it and adds the sweep to it. +func (b *Batcher) launchNewBatch(ctx context.Context, sweep *sweep) error { + // Spin up a fresh batch. batch, err := b.spinUpBatch(ctx) if err != nil { return err @@ -878,6 +902,7 @@ func (b *Batcher) loadSweep(ctx context.Context, swapHash lntypes.Hash, isExternalAddr: s.IsExternalAddr, destAddr: s.DestAddr, minFeeRate: minFeeRate, + nonCoopHint: s.NonCoopHint, }, nil }