builder.go

@@ -49,7 +49,7 @@ var (
 	nullCodeHash      = crypto.Keccak256([]byte{})
 	zeroHash          common.Hash
 
-	defaultSubtrieWorkers = 8
+	defaultSubtrieWorkers uint = 1
 )
 
 // Builder interface exposes the method for building a state diff between two blocks
@@ -61,7 +61,7 @@ type Builder interface {
 type StateDiffBuilder struct {
 	// state cache is safe for concurrent reads
 	stateCache     adapt.StateView
-	subtrieWorkers int
+	subtrieWorkers uint
 }
 
 type accountUpdate struct {
@@ -88,13 +88,22 @@ func syncedAppender[T any](to *[]T) func(T) error {
 }
 
 // NewBuilder is used to create a statediff builder
-func NewBuilder(stateCache adapt.StateView) Builder {
+func NewBuilder(stateCache adapt.StateView) *StateDiffBuilder {
 	return &StateDiffBuilder{
 		stateCache:     stateCache,
 		subtrieWorkers: defaultSubtrieWorkers,
 	}
 }
 
+// SetSubtrieWorkers sets the number of disjoint subtries to divide among parallel workers.
+// Passing 0 will reset this to the default value.
+func (sdb *StateDiffBuilder) SetSubtrieWorkers(n uint) {
+	if n == 0 {
+		n = defaultSubtrieWorkers
+	}
+	sdb.subtrieWorkers = n
+}
+
 // BuildStateDiffObject builds a statediff object from two blocks and the provided parameters
 func (sdb *StateDiffBuilder) BuildStateDiffObject(args Args, params Params) (sdtypes.StateObject, error) {
 	defer metrics.UpdateDuration(time.Now(), metrics.IndexerMetrics.BuildStateDiffObjectTimer)
@@ -134,8 +143,8 @@ func (sdb *StateDiffBuilder) WriteStateDiff(
 	logger := log.New("hash", args.BlockHash, "number", args.BlockNumber)
 	// errgroup will cancel if any gr fails
 	g, ctx := errgroup.WithContext(context.Background())
-	for i := 0; i < sdb.subtrieWorkers; i++ {
+	for i := uint(0); i < sdb.subtrieWorkers; i++ {
-		func(subdiv int) {
+		func(subdiv uint) {
 			g.Go(func() error {
 				a, b := subitersA[subdiv], subitersB[subdiv]
 				return sdb.processAccounts(ctx,

builder_test.go

@@ -795,13 +795,13 @@ func TestBuilder(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(),
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
-		tests, params, test_helpers.CheckedRoots{
+	test_helpers.CheckedRoots{
 		block0: bankAccountAtBlock0LeafNode,
 		block1: block1BranchRootNode,
 		block2: block2BranchRootNode,
 		block3: block3BranchRootNode,
-		})
+	}.Check(t)
 }
 
 func TestBuilderWithWatchedAddressList(t *testing.T) {
@@ -1009,12 +1009,13 @@ func TestBuilderWithWatchedAddressList(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, test_helpers.CheckedRoots{
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
+	test_helpers.CheckedRoots{
 		block0: bankAccountAtBlock0LeafNode,
 		block1: block1BranchRootNode,
 		block2: block2BranchRootNode,
 		block3: block3BranchRootNode,
-	})
+	}.Check(t)
 }
 
 func TestBuilderWithRemovedAccountAndStorage(t *testing.T) {
@@ -1259,11 +1260,12 @@ func TestBuilderWithRemovedAccountAndStorage(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, test_helpers.CheckedRoots{
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
+	test_helpers.CheckedRoots{
 		block4: block4BranchRootNode,
 		block5: block5BranchRootNode,
 		block6: block6BranchRootNode,
-	})
+	}.Check(t)
 }
 
 func TestBuilderWithRemovedNonWatchedAccount(t *testing.T) {
@@ -1393,11 +1395,12 @@ func TestBuilderWithRemovedNonWatchedAccount(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, test_helpers.CheckedRoots{
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
+	test_helpers.CheckedRoots{
 		block4: block4BranchRootNode,
 		block5: block5BranchRootNode,
 		block6: block6BranchRootNode,
-	})
+	}.Check(t)
 }
 
 func TestBuilderWithRemovedWatchedAccount(t *testing.T) {
@@ -1596,11 +1599,12 @@ func TestBuilderWithRemovedWatchedAccount(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, test_helpers.CheckedRoots{
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
+	test_helpers.CheckedRoots{
 		block4: block4BranchRootNode,
 		block5: block5BranchRootNode,
 		block6: block6BranchRootNode,
-	})
+	}.Check(t)
 }
 
 var (
@@ -1823,10 +1827,11 @@ func TestBuilderWithMovedAccount(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, test_helpers.CheckedRoots{
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
+	test_helpers.CheckedRoots{
 		block1: block01BranchRootNode,
 		block2: bankAccountAtBlock02LeafNode,
-	})
+	}.Check(t)
 }
 
 /*
@@ -2349,11 +2354,12 @@ func TestBuilderWithInternalizedLeafNode(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, test_helpers.CheckedRoots{
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
+	test_helpers.CheckedRoots{
 		block1: block1bBranchRootNode,
 		block2: block2bBranchRootNode,
 		block3: block3bBranchRootNode,
-	})
+	}.Check(t)
 }
 
 func TestBuilderWithInternalizedLeafNodeAndWatchedAddress(t *testing.T) {
@@ -2550,11 +2556,12 @@ func TestBuilderWithInternalizedLeafNodeAndWatchedAddress(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, test_helpers.CheckedRoots{
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
+	test_helpers.CheckedRoots{
 		block1: block1bBranchRootNode,
 		block2: block2bBranchRootNode,
 		block3: block3bBranchRootNode,
-	})
+	}.Check(t)
 }
 
 /*

mainnet_tests/builder_test.go

@@ -622,11 +622,10 @@ func TestBuilderOnMainnetBlocks(t *testing.T) {
 		},
 	}
 
-	test_helpers.RunBuilderTests(t,
+	test_helpers.RunBuilderTests(t, chain.StateCache(), tests, params, []uint{1, 8, 32})
-		chain.StateCache(),
+	test_helpers.CheckedRoots{
-		tests, params, test_helpers.CheckedRoots{
 		block1: block1RootBranchNode,
 		block2: block2RootBranchNode,
 		block3: block3RootBranchNode,
-		})
+	}.Check(t)
 }

test_helpers/builder.go

@@ -2,6 +2,7 @@ package test_helpers
 
 import (
 	"bytes"
+	"fmt"
 	"sort"
 	"testing"
 
@@ -20,18 +21,20 @@ type TestCase struct {
 	Expected *sdtypes.StateObject
 }
 
-type CheckedRoots = map[*types.Block][]byte
+type CheckedRoots map[*types.Block][]byte
 
 func RunBuilderTests(
 	t *testing.T,
 	sdb state.Database,
 	tests []TestCase,
 	params statediff.Params,
-	roots CheckedRoots,
+	subtrieCounts []uint,
 ) {
 	builder := statediff.NewBuilder(adapt.GethStateView(sdb))
 	for _, test := range tests {
-		t.Run(test.Name, func(t *testing.T) {
+		for _, subtries := range subtrieCounts {
+			t.Run(fmt.Sprintf("%s with %d subtries", test.Name, subtries), func(t *testing.T) {
+				builder.SetSubtrieWorkers(subtries)
 				diff, err := builder.BuildStateDiffObject(test.Args, params)
 				if err != nil {
 					t.Error(err)
@@ -42,6 +45,10 @@ func RunBuilderTests(
 				require.Equal(t, *test.Expected, diff)
 			})
 		}
+	}
+}
+
+func (roots CheckedRoots) Check(t *testing.T) {
 	// Let's also confirm that our root state nodes form the state root hash in the headers
 	for block, node := range roots {
 		require.Equal(t, block.Root(), crypto.Keccak256Hash(node),