diff --git a/eth/filters/filter.go b/eth/filters/filter.go
index 0a70c9ece..8d80647fc 100644
--- a/eth/filters/filter.go
+++ b/eth/filters/filter.go
@@ -34,8 +34,8 @@ type Filter struct {
 	addresses []common.Address
 	topics    [][]common.Hash
 
-	block      common.Hash // Block hash if filtering a single block
-	begin, end int64       // Range interval if filtering multiple blocks
+	block      *common.Hash // Block hash if filtering a single block
+	begin, end int64        // Range interval if filtering multiple blocks
 
 	matcher *bloombits.Matcher
 }
@@ -78,7 +78,7 @@ func (sys *FilterSystem) NewRangeFilter(begin, end int64, addresses []common.Add
 func (sys *FilterSystem) NewBlockFilter(block common.Hash, addresses []common.Address, topics [][]common.Hash) *Filter {
 	// Create a generic filter and convert it into a block filter
 	filter := newFilter(sys, addresses, topics)
-	filter.block = block
+	filter.block = &block
 	return filter
 }
 
@@ -96,8 +96,8 @@ func newFilter(sys *FilterSystem, addresses []common.Address, topics [][]common.
 // first block that contains matches, updating the start of the filter accordingly.
 func (f *Filter) Logs(ctx context.Context) ([]*types.Log, error) {
 	// If we're doing singleton block filtering, execute and return
-	if f.block != (common.Hash{}) {
-		header, err := f.sys.backend.HeaderByHash(ctx, f.block)
+	if f.block != nil {
+		header, err := f.sys.backend.HeaderByHash(ctx, *f.block)
 		if err != nil {
 			return nil, err
 		}
diff --git a/eth/handler.go b/eth/handler.go
index 4224a9f33..143147b0c 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -391,11 +391,16 @@ func (h *handler) runEthPeer(peer *eth.Peer, handler eth.Handler) error {
 	if h.checkpointHash != (common.Hash{}) {
 		// Request the peer's checkpoint header for chain height/weight validation
 		resCh := make(chan *eth.Response)
-		if _, err := peer.RequestHeadersByNumber(h.checkpointNumber, 1, 0, false, resCh); err != nil {
+
+		req, err := peer.RequestHeadersByNumber(h.checkpointNumber, 1, 0, false, resCh)
+		if err != nil {
 			return err
 		}
 		// Start a timer to disconnect if the peer doesn't reply in time
 		go func() {
+			// Ensure the request gets cancelled in case of error/drop
+			defer req.Close()
+
 			timeout := time.NewTimer(syncChallengeTimeout)
 			defer timeout.Stop()
 
@@ -437,10 +442,15 @@ func (h *handler) runEthPeer(peer *eth.Peer, handler eth.Handler) error {
 	// If we have any explicit peer required block hashes, request them
 	for number, hash := range h.requiredBlocks {
 		resCh := make(chan *eth.Response)
-		if _, err := peer.RequestHeadersByNumber(number, 1, 0, false, resCh); err != nil {
+
+		req, err := peer.RequestHeadersByNumber(number, 1, 0, false, resCh)
+		if err != nil {
 			return err
 		}
-		go func(number uint64, hash common.Hash) {
+		go func(number uint64, hash common.Hash, req *eth.Request) {
+			// Ensure the request gets cancelled in case of error/drop
+			defer req.Close()
+
 			timeout := time.NewTimer(syncChallengeTimeout)
 			defer timeout.Stop()
 
@@ -469,7 +479,7 @@ func (h *handler) runEthPeer(peer *eth.Peer, handler eth.Handler) error {
 				peer.Log().Warn("Required block challenge timed out, dropping", "addr", peer.RemoteAddr(), "type", peer.Name())
 				h.removePeer(peer.ID())
 			}
-		}(number, hash)
+		}(number, hash, req)
 	}
 	// Handle incoming messages until the connection is torn down
 	return handler(peer)
diff --git a/eth/protocols/snap/sync.go b/eth/protocols/snap/sync.go
index deaa4456e..eb8260bf7 100644
--- a/eth/protocols/snap/sync.go
+++ b/eth/protocols/snap/sync.go
@@ -21,10 +21,12 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	gomath "math"
 	"math/big"
 	"math/rand"
 	"sort"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -78,6 +80,29 @@ const (
 	// and waste round trip times. If it's too high, we're capping responses and
 	// waste bandwidth.
 	maxTrieRequestCount = maxRequestSize / 512
+
+	// trienodeHealRateMeasurementImpact is the impact a single measurement has on
+	// the local node's trienode processing capacity. A value closer to 0 reacts
+	// slower to sudden changes, but it is also more stable against temporary hiccups.
+	trienodeHealRateMeasurementImpact = 0.005
+
+	// minTrienodeHealThrottle is the minimum divisor for throttling trie node
+	// heal requests to avoid overloading the local node and exessively expanding
+	// the state trie bedth wise.
+	minTrienodeHealThrottle = 1
+
+	// maxTrienodeHealThrottle is the maximum divisor for throttling trie node
+	// heal requests to avoid overloading the local node and exessively expanding
+	// the state trie bedth wise.
+	maxTrienodeHealThrottle = maxTrieRequestCount
+
+	// trienodeHealThrottleIncrease is the multiplier for the throttle when the
+	// rate of arriving data is higher than the rate of processing it.
+	trienodeHealThrottleIncrease = 1.33
+
+	// trienodeHealThrottleDecrease is the divisor for the throttle when the
+	// rate of arriving data is lower than the rate of processing it.
+	trienodeHealThrottleDecrease = 1.25
 )
 
 var (
@@ -431,6 +456,11 @@ type Syncer struct {
 	trienodeHealReqs map[uint64]*trienodeHealRequest // Trie node requests currently running
 	bytecodeHealReqs map[uint64]*bytecodeHealRequest // Bytecode requests currently running
 
+	trienodeHealRate      float64   // Average heal rate for processing trie node data
+	trienodeHealPend      uint64    // Number of trie nodes currently pending for processing
+	trienodeHealThrottle  float64   // Divisor for throttling the amount of trienode heal data requested
+	trienodeHealThrottled time.Time // Timestamp the last time the throttle was updated
+
 	trienodeHealSynced uint64             // Number of state trie nodes downloaded
 	trienodeHealBytes  common.StorageSize // Number of state trie bytes persisted to disk
 	trienodeHealDups   uint64             // Number of state trie nodes already processed
@@ -476,9 +506,10 @@ func NewSyncer(db ethdb.KeyValueStore) *Syncer {
 		trienodeHealIdlers: make(map[string]struct{}),
 		bytecodeHealIdlers: make(map[string]struct{}),
 
-		trienodeHealReqs: make(map[uint64]*trienodeHealRequest),
-		bytecodeHealReqs: make(map[uint64]*bytecodeHealRequest),
-		stateWriter:      db.NewBatch(),
+		trienodeHealReqs:     make(map[uint64]*trienodeHealRequest),
+		bytecodeHealReqs:     make(map[uint64]*bytecodeHealRequest),
+		trienodeHealThrottle: maxTrienodeHealThrottle, // Tune downward instead of insta-filling with junk
+		stateWriter:          db.NewBatch(),
 
 		extProgress: new(SyncProgress),
 	}
@@ -1321,6 +1352,10 @@ func (s *Syncer) assignTrienodeHealTasks(success chan *trienodeHealResponse, fai
 		if cap > maxTrieRequestCount {
 			cap = maxTrieRequestCount
 		}
+		cap = int(float64(cap) / s.trienodeHealThrottle)
+		if cap <= 0 {
+			cap = 1
+		}
 		var (
 			hashes   = make([]common.Hash, 0, cap)
 			paths    = make([]string, 0, cap)
@@ -2090,6 +2125,10 @@ func (s *Syncer) processStorageResponse(res *storageResponse) {
 // processTrienodeHealResponse integrates an already validated trienode response
 // into the healer tasks.
 func (s *Syncer) processTrienodeHealResponse(res *trienodeHealResponse) {
+	var (
+		start = time.Now()
+		fills int
+	)
 	for i, hash := range res.hashes {
 		node := res.nodes[i]
 
@@ -2098,6 +2137,8 @@ func (s *Syncer) processTrienodeHealResponse(res *trienodeHealResponse) {
 			res.task.trieTasks[res.paths[i]] = res.hashes[i]
 			continue
 		}
+		fills++
+
 		// Push the trie node into the state syncer
 		s.trienodeHealSynced++
 		s.trienodeHealBytes += common.StorageSize(len(node))
@@ -2121,6 +2162,50 @@ func (s *Syncer) processTrienodeHealResponse(res *trienodeHealResponse) {
 		log.Crit("Failed to persist healing data", "err", err)
 	}
 	log.Debug("Persisted set of healing data", "type", "trienodes", "bytes", common.StorageSize(batch.ValueSize()))
+
+	// Calculate the processing rate of one filled trie node
+	rate := float64(fills) / (float64(time.Since(start)) / float64(time.Second))
+
+	// Update the currently measured trienode queueing and processing throughput.
+	//
+	// The processing rate needs to be updated uniformly independent if we've
+	// processed 1x100 trie nodes or 100x1 to keep the rate consistent even in
+	// the face of varying network packets. As such, we cannot just measure the
+	// time it took to process N trie nodes and update once, we need one update
+	// per trie node.
+	//
+	// Naively, that would be:
+	//
+	//   for i:=0; i<fills; i++ {
+	//     healRate = (1-measurementImpact)*oldRate + measurementImpact*newRate
+	//   }
+	//
+	// Essentially, a recursive expansion of HR = (1-MI)*HR + MI*NR.
+	//
+	// We can expand that formula for the Nth item as:
+	//   HR(N) = (1-MI)^N*OR + (1-MI)^(N-1)*MI*NR + (1-MI)^(N-2)*MI*NR + ... + (1-MI)^0*MI*NR
+	//
+	// The above is a geometric sequence that can be summed to:
+	//   HR(N) = (1-MI)^N*(OR-NR) + NR
+	s.trienodeHealRate = gomath.Pow(1-trienodeHealRateMeasurementImpact, float64(fills))*(s.trienodeHealRate-rate) + rate
+
+	pending := atomic.LoadUint64(&s.trienodeHealPend)
+	if time.Since(s.trienodeHealThrottled) > time.Second {
+		// Periodically adjust the trie node throttler
+		if float64(pending) > 2*s.trienodeHealRate {
+			s.trienodeHealThrottle *= trienodeHealThrottleIncrease
+		} else {
+			s.trienodeHealThrottle /= trienodeHealThrottleDecrease
+		}
+		if s.trienodeHealThrottle > maxTrienodeHealThrottle {
+			s.trienodeHealThrottle = maxTrienodeHealThrottle
+		} else if s.trienodeHealThrottle < minTrienodeHealThrottle {
+			s.trienodeHealThrottle = minTrienodeHealThrottle
+		}
+		s.trienodeHealThrottled = time.Now()
+
+		log.Debug("Updated trie node heal throttler", "rate", s.trienodeHealRate, "pending", pending, "throttle", s.trienodeHealThrottle)
+	}
 }
 
 // processBytecodeHealResponse integrates an already validated bytecode response
@@ -2248,14 +2333,18 @@ func (s *Syncer) OnAccounts(peer SyncPeer, id uint64, hashes []common.Hash, acco
 	// Whether or not the response is valid, we can mark the peer as idle and
 	// notify the scheduler to assign a new task. If the response is invalid,
 	// we'll drop the peer in a bit.
+	defer func() {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+		if _, ok := s.peers[peer.ID()]; ok {
+			s.accountIdlers[peer.ID()] = struct{}{}
+		}
+		select {
+		case s.update <- struct{}{}:
+		default:
+		}
+	}()
 	s.lock.Lock()
-	if _, ok := s.peers[peer.ID()]; ok {
-		s.accountIdlers[peer.ID()] = struct{}{}
-	}
-	select {
-	case s.update <- struct{}{}:
-	default:
-	}
 	// Ensure the response is for a valid request
 	req, ok := s.accountReqs[id]
 	if !ok {
@@ -2360,14 +2449,18 @@ func (s *Syncer) onByteCodes(peer SyncPeer, id uint64, bytecodes [][]byte) error
 	// Whether or not the response is valid, we can mark the peer as idle and
 	// notify the scheduler to assign a new task. If the response is invalid,
 	// we'll drop the peer in a bit.
+	defer func() {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+		if _, ok := s.peers[peer.ID()]; ok {
+			s.bytecodeIdlers[peer.ID()] = struct{}{}
+		}
+		select {
+		case s.update <- struct{}{}:
+		default:
+		}
+	}()
 	s.lock.Lock()
-	if _, ok := s.peers[peer.ID()]; ok {
-		s.bytecodeIdlers[peer.ID()] = struct{}{}
-	}
-	select {
-	case s.update <- struct{}{}:
-	default:
-	}
 	// Ensure the response is for a valid request
 	req, ok := s.bytecodeReqs[id]
 	if !ok {
@@ -2469,14 +2562,18 @@ func (s *Syncer) OnStorage(peer SyncPeer, id uint64, hashes [][]common.Hash, slo
 	// Whether or not the response is valid, we can mark the peer as idle and
 	// notify the scheduler to assign a new task. If the response is invalid,
 	// we'll drop the peer in a bit.
+	defer func() {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+		if _, ok := s.peers[peer.ID()]; ok {
+			s.storageIdlers[peer.ID()] = struct{}{}
+		}
+		select {
+		case s.update <- struct{}{}:
+		default:
+		}
+	}()
 	s.lock.Lock()
-	if _, ok := s.peers[peer.ID()]; ok {
-		s.storageIdlers[peer.ID()] = struct{}{}
-	}
-	select {
-	case s.update <- struct{}{}:
-	default:
-	}
 	// Ensure the response is for a valid request
 	req, ok := s.storageReqs[id]
 	if !ok {
@@ -2596,14 +2693,18 @@ func (s *Syncer) OnTrieNodes(peer SyncPeer, id uint64, trienodes [][]byte) error
 	// Whether or not the response is valid, we can mark the peer as idle and
 	// notify the scheduler to assign a new task. If the response is invalid,
 	// we'll drop the peer in a bit.
+	defer func() {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+		if _, ok := s.peers[peer.ID()]; ok {
+			s.trienodeHealIdlers[peer.ID()] = struct{}{}
+		}
+		select {
+		case s.update <- struct{}{}:
+		default:
+		}
+	}()
 	s.lock.Lock()
-	if _, ok := s.peers[peer.ID()]; ok {
-		s.trienodeHealIdlers[peer.ID()] = struct{}{}
-	}
-	select {
-	case s.update <- struct{}{}:
-	default:
-	}
 	// Ensure the response is for a valid request
 	req, ok := s.trienodeHealReqs[id]
 	if !ok {
@@ -2639,10 +2740,12 @@ func (s *Syncer) OnTrieNodes(peer SyncPeer, id uint64, trienodes [][]byte) error
 
 	// Cross reference the requested trienodes with the response to find gaps
 	// that the serving node is missing
-	hasher := sha3.NewLegacyKeccak256().(crypto.KeccakState)
-	hash := make([]byte, 32)
-
-	nodes := make([][]byte, len(req.hashes))
+	var (
+		hasher = sha3.NewLegacyKeccak256().(crypto.KeccakState)
+		hash   = make([]byte, 32)
+		nodes  = make([][]byte, len(req.hashes))
+		fills  uint64
+	)
 	for i, j := 0, 0; i < len(trienodes); i++ {
 		// Find the next hash that we've been served, leaving misses with nils
 		hasher.Reset()
@@ -2654,16 +2757,22 @@ func (s *Syncer) OnTrieNodes(peer SyncPeer, id uint64, trienodes [][]byte) error
 		}
 		if j < len(req.hashes) {
 			nodes[j] = trienodes[i]
+			fills++
 			j++
 			continue
 		}
 		// We've either ran out of hashes, or got unrequested data
 		logger.Warn("Unexpected healing trienodes", "count", len(trienodes)-i)
+
 		// Signal this request as failed, and ready for rescheduling
 		s.scheduleRevertTrienodeHealRequest(req)
 		return errors.New("unexpected healing trienode")
 	}
 	// Response validated, send it to the scheduler for filling
+	atomic.AddUint64(&s.trienodeHealPend, fills)
+	defer func() {
+		atomic.AddUint64(&s.trienodeHealPend, ^(fills - 1))
+	}()
 	response := &trienodeHealResponse{
 		paths:  req.paths,
 		task:   req.task,
@@ -2691,14 +2800,18 @@ func (s *Syncer) onHealByteCodes(peer SyncPeer, id uint64, bytecodes [][]byte) e
 	// Whether or not the response is valid, we can mark the peer as idle and
 	// notify the scheduler to assign a new task. If the response is invalid,
 	// we'll drop the peer in a bit.
+	defer func() {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+		if _, ok := s.peers[peer.ID()]; ok {
+			s.bytecodeHealIdlers[peer.ID()] = struct{}{}
+		}
+		select {
+		case s.update <- struct{}{}:
+		default:
+		}
+	}()
 	s.lock.Lock()
-	if _, ok := s.peers[peer.ID()]; ok {
-		s.bytecodeHealIdlers[peer.ID()] = struct{}{}
-	}
-	select {
-	case s.update <- struct{}{}:
-	default:
-	}
 	// Ensure the response is for a valid request
 	req, ok := s.bytecodeHealReqs[id]
 	if !ok {
diff --git a/params/version.go b/params/version.go
index 3b5978e84..d9a395851 100644
--- a/params/version.go
+++ b/params/version.go
@@ -23,7 +23,7 @@ import (
 const (
 	VersionMajor = 1        // Major version component of the current release
 	VersionMinor = 10       // Minor version component of the current release
-	VersionPatch = 25       // Patch version component of the current release
+	VersionPatch = 26       // Patch version component of the current release
 	VersionMeta  = "stable" // Version metadata to append to the version string
 )
 
diff --git a/rpc/client.go b/rpc/client.go
index d3ce02977..fcd31319a 100644
--- a/rpc/client.go
+++ b/rpc/client.go
@@ -31,6 +31,7 @@ import (
 )
 
 var (
+	ErrBadResult                 = errors.New("bad result in JSON-RPC response")
 	ErrClientQuit                = errors.New("client is closed")
 	ErrNoResult                  = errors.New("no result in JSON-RPC response")
 	ErrSubscriptionQueueOverflow = errors.New("subscription queue overflow")
diff --git a/rpc/client_test.go b/rpc/client_test.go
index 04c847d0d..5ae549d86 100644
--- a/rpc/client_test.go
+++ b/rpc/client_test.go
@@ -19,6 +19,7 @@ package rpc
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"math/rand"
 	"net"
@@ -144,6 +145,53 @@ func TestClientBatchRequest(t *testing.T) {
 	}
 }
 
+func TestClientBatchRequest_len(t *testing.T) {
+	b, err := json.Marshal([]jsonrpcMessage{
+		{Version: "2.0", ID: json.RawMessage("1"), Method: "foo", Result: json.RawMessage(`"0x1"`)},
+		{Version: "2.0", ID: json.RawMessage("2"), Method: "bar", Result: json.RawMessage(`"0x2"`)},
+	})
+	if err != nil {
+		t.Fatal("failed to encode jsonrpc message:", err)
+	}
+	s := httptest.NewServer(http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+		_, err := rw.Write(b)
+		if err != nil {
+			t.Error("failed to write response:", err)
+		}
+	}))
+	t.Cleanup(s.Close)
+
+	client, err := Dial(s.URL)
+	if err != nil {
+		t.Fatal("failed to dial test server:", err)
+	}
+	defer client.Close()
+
+	t.Run("too-few", func(t *testing.T) {
+		batch := []BatchElem{
+			{Method: "foo"},
+			{Method: "bar"},
+			{Method: "baz"},
+		}
+		ctx, cancelFn := context.WithTimeout(context.Background(), time.Second)
+		defer cancelFn()
+		if err := client.BatchCallContext(ctx, batch); !errors.Is(err, ErrBadResult) {
+			t.Errorf("expected %q but got: %v", ErrBadResult, err)
+		}
+	})
+
+	t.Run("too-many", func(t *testing.T) {
+		batch := []BatchElem{
+			{Method: "foo"},
+		}
+		ctx, cancelFn := context.WithTimeout(context.Background(), time.Second)
+		defer cancelFn()
+		if err := client.BatchCallContext(ctx, batch); !errors.Is(err, ErrBadResult) {
+			t.Errorf("expected %q but got: %v", ErrBadResult, err)
+		}
+	})
+}
+
 func TestClientNotify(t *testing.T) {
 	server := newTestServer()
 	defer server.Stop()
diff --git a/rpc/http.go b/rpc/http.go
index 858d80858..b82ea2707 100644
--- a/rpc/http.go
+++ b/rpc/http.go
@@ -173,6 +173,9 @@ func (c *Client) sendBatchHTTP(ctx context.Context, op *requestOp, msgs []*jsonr
 	if err := json.NewDecoder(respBody).Decode(&respmsgs); err != nil {
 		return err
 	}
+	if len(respmsgs) != len(msgs) {
+		return fmt.Errorf("batch has %d requests but response has %d: %w", len(msgs), len(respmsgs), ErrBadResult)
+	}
 	for i := 0; i < len(respmsgs); i++ {
 		op.resp <- &respmsgs[i]
 	}
diff --git a/trie/sync.go b/trie/sync.go
index 303fcbfa2..862ce7e16 100644
--- a/trie/sync.go
+++ b/trie/sync.go
@@ -19,6 +19,7 @@ package trie
 import (
 	"errors"
 	"fmt"
+	"sync"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/prque"
@@ -381,11 +382,11 @@ func (s *Sync) scheduleCodeRequest(req *codeRequest) {
 // retrieval scheduling.
 func (s *Sync) children(req *nodeRequest, object node) ([]*nodeRequest, error) {
 	// Gather all the children of the node, irrelevant whether known or not
-	type child struct {
+	type childNode struct {
 		path []byte
 		node node
 	}
-	var children []child
+	var children []childNode
 
 	switch node := (object).(type) {
 	case *shortNode:
@@ -393,14 +394,14 @@ func (s *Sync) children(req *nodeRequest, object node) ([]*nodeRequest, error) {
 		if hasTerm(key) {
 			key = key[:len(key)-1]
 		}
-		children = []child{{
+		children = []childNode{{
 			node: node.Val,
 			path: append(append([]byte(nil), req.path...), key...),
 		}}
 	case *fullNode:
 		for i := 0; i < 17; i++ {
 			if node.Children[i] != nil {
-				children = append(children, child{
+				children = append(children, childNode{
 					node: node.Children[i],
 					path: append(append([]byte(nil), req.path...), byte(i)),
 				})
@@ -410,7 +411,10 @@ func (s *Sync) children(req *nodeRequest, object node) ([]*nodeRequest, error) {
 		panic(fmt.Sprintf("unknown node: %+v", node))
 	}
 	// Iterate over the children, and request all unknown ones
-	requests := make([]*nodeRequest, 0, len(children))
+	var (
+		missing = make(chan *nodeRequest, len(children))
+		pending sync.WaitGroup
+	)
 	for _, child := range children {
 		// Notify any external watcher of a new key/value node
 		if req.callback != nil {
@@ -433,19 +437,36 @@ func (s *Sync) children(req *nodeRequest, object node) ([]*nodeRequest, error) {
 			if s.membatch.hasNode(child.path) {
 				continue
 			}
-			// If database says duplicate, then at least the trie node is present
-			// and we hold the assumption that it's NOT legacy contract code.
-			chash := common.BytesToHash(node)
-			if rawdb.HasTrieNode(s.database, chash) {
-				continue
-			}
-			// Locally unknown node, schedule for retrieval
-			requests = append(requests, &nodeRequest{
-				path:     child.path,
-				hash:     chash,
-				parent:   req,
-				callback: req.callback,
-			})
+			// Check the presence of children concurrently
+			pending.Add(1)
+			go func(child childNode) {
+				defer pending.Done()
+
+				// If database says duplicate, then at least the trie node is present
+				// and we hold the assumption that it's NOT legacy contract code.
+				chash := common.BytesToHash(node)
+				if rawdb.HasTrieNode(s.database, chash) {
+					return
+				}
+				// Locally unknown node, schedule for retrieval
+				missing <- &nodeRequest{
+					path:     child.path,
+					hash:     chash,
+					parent:   req,
+					callback: req.callback,
+				}
+			}(child)
+		}
+	}
+	pending.Wait()
+
+	requests := make([]*nodeRequest, 0, len(children))
+	for done := false; !done; {
+		select {
+		case miss := <-missing:
+			requests = append(requests, miss)
+		default:
+			done = true
 		}
 	}
 	return requests, nil