Use singlethreaded execution when there is only one CPU.

core/state/statedb.go

@@ -166,8 +166,6 @@ type StateDB struct {
 	StorageUpdated atomic.Int64
 	AccountDeleted int
 	StorageDeleted atomic.Int64
-
-	singlethreaded bool
 }
 
 // New creates a new state from a given trie.
@@ -197,10 +195,6 @@ func New(root common.Hash, db Database, snaps *snapshot.Tree) (*StateDB, error)
 	return sdb, nil
 }
 
-func (s *StateDB) MakeSingleThreaded() {
-	s.singlethreaded = true
-}
-
 // SetLogger sets the logger for account update hooks.
 func (s *StateDB) SetLogger(l *tracing.Hooks) {
 	s.logger = l
@@ -858,7 +852,7 @@ func (s *StateDB) IntermediateRoot(deleteEmptyObjects bool) common.Hash {
 	var (
 		start = time.Now()
 	)
-	workers := newWorkerGroup(s.singlethreaded)
+	workers := newWorkerGroup()
 	if s.db.TrieDB().IsVerkle() {
 		// Whilst MPT storage tries are independent, Verkle has one single trie
 		// for all the accounts and all the storage slots merged together. The
@@ -1233,7 +1227,7 @@ func (s *StateDB) commit(deleteEmptyObjects bool) (*stateUpdate, error) {
 		start = time.Now()
 		root  common.Hash
 	)
-	workers := newWorkerGroup(s.singlethreaded)
+	workers := newWorkerGroup()
 	// Schedule the account trie first since that will be the biggest, so give
 	// it the most time to crunch.
 	//

core/state/workers.go

@@ -2,6 +2,7 @@ package state
 
 import (
 	"errors"
+	"runtime"
 
 	"golang.org/x/sync/errgroup"
 )
@@ -12,8 +13,8 @@ type workerGroup interface {
 	Wait() error
 }
 
-func newWorkerGroup(singlethreaded bool) workerGroup {
-	if singlethreaded {
+func newWorkerGroup() workerGroup {
+	if runtime.NumCPU() == 1 {
 		return &inlineWorkerGroup{}
 	} else {
 		var grp errgroup.Group