eth/protocols/snap: skip retrieval for completed storages (#29378)

* eth/protocols/snap: skip retrieval for completed storages

* eth/protocols/snap: address comments from peter

* eth/protocols/snap: add comments

eth/protocols/snap/metrics.go

@@ -54,4 +54,9 @@ var (
 	// skipStorageHealingGauge is the metric to track how many storages are retrieved
 	// in multiple requests but healing is not necessary.
 	skipStorageHealingGauge = metrics.NewRegisteredGauge("eth/protocols/snap/sync/storage/noheal", nil)
+
+	// largeStorageDiscardGauge is the metric to track how many chunked storages are
+	// discarded during the snap sync.
+	largeStorageDiscardGauge = metrics.NewRegisteredGauge("eth/protocols/snap/sync/storage/chunk/discard", nil)
+	largeStorageResumedGauge = metrics.NewRegisteredGauge("eth/protocols/snap/sync/storage/chunk/resume", nil)
 )

eth/protocols/snap/progress_test.go

@@ -0,0 +1,154 @@
+// Copyright 2024 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package snap
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+// Legacy sync progress definitions
+type legacyStorageTask struct {
+	Next common.Hash // Next account to sync in this interval
+	Last common.Hash // Last account to sync in this interval
+}
+
+type legacyAccountTask struct {
+	Next     common.Hash                          // Next account to sync in this interval
+	Last     common.Hash                          // Last account to sync in this interval
+	SubTasks map[common.Hash][]*legacyStorageTask // Storage intervals needing fetching for large contracts
+}
+
+type legacyProgress struct {
+	Tasks []*legacyAccountTask // The suspended account tasks (contract tasks within)
+}
+
+func compareProgress(a legacyProgress, b SyncProgress) bool {
+	if len(a.Tasks) != len(b.Tasks) {
+		return false
+	}
+	for i := 0; i < len(a.Tasks); i++ {
+		if a.Tasks[i].Next != b.Tasks[i].Next {
+			return false
+		}
+		if a.Tasks[i].Last != b.Tasks[i].Last {
+			return false
+		}
+		// new fields are not checked here
+
+		if len(a.Tasks[i].SubTasks) != len(b.Tasks[i].SubTasks) {
+			return false
+		}
+		for addrHash, subTasksA := range a.Tasks[i].SubTasks {
+			subTasksB, ok := b.Tasks[i].SubTasks[addrHash]
+			if !ok || len(subTasksB) != len(subTasksA) {
+				return false
+			}
+			for j := 0; j < len(subTasksA); j++ {
+				if subTasksA[j].Next != subTasksB[j].Next {
+					return false
+				}
+				if subTasksA[j].Last != subTasksB[j].Last {
+					return false
+				}
+			}
+		}
+	}
+	return true
+}
+
+func makeLegacyProgress() legacyProgress {
+	return legacyProgress{
+		Tasks: []*legacyAccountTask{
+			{
+				Next: common.Hash{},
+				Last: common.Hash{0x77},
+				SubTasks: map[common.Hash][]*legacyStorageTask{
+					common.Hash{0x1}: {
+						{
+							Next: common.Hash{},
+							Last: common.Hash{0xff},
+						},
+					},
+				},
+			},
+			{
+				Next: common.Hash{0x88},
+				Last: common.Hash{0xff},
+			},
+		},
+	}
+}
+
+func convertLegacy(legacy legacyProgress) SyncProgress {
+	var progress SyncProgress
+	for i, task := range legacy.Tasks {
+		subTasks := make(map[common.Hash][]*storageTask)
+		for owner, list := range task.SubTasks {
+			var cpy []*storageTask
+			for i := 0; i < len(list); i++ {
+				cpy = append(cpy, &storageTask{
+					Next: list[i].Next,
+					Last: list[i].Last,
+				})
+			}
+			subTasks[owner] = cpy
+		}
+		accountTask := &accountTask{
+			Next:     task.Next,
+			Last:     task.Last,
+			SubTasks: subTasks,
+		}
+		if i == 0 {
+			accountTask.StorageCompleted = []common.Hash{{0xaa}, {0xbb}} // fulfill new fields
+		}
+		progress.Tasks = append(progress.Tasks, accountTask)
+	}
+	return progress
+}
+
+func TestSyncProgressCompatibility(t *testing.T) {
+	// Decode serialized bytes of legacy progress, backward compatibility
+	legacy := makeLegacyProgress()
+	blob, err := json.Marshal(legacy)
+	if err != nil {
+		t.Fatalf("Failed to marshal progress %v", err)
+	}
+	var dec SyncProgress
+	if err := json.Unmarshal(blob, &dec); err != nil {
+		t.Fatalf("Failed to unmarshal progress %v", err)
+	}
+	if !compareProgress(legacy, dec) {
+		t.Fatal("sync progress is not backward compatible")
+	}
+
+	// Decode serialized bytes of new format progress
+	progress := convertLegacy(legacy)
+	blob, err = json.Marshal(progress)
+	if err != nil {
+		t.Fatalf("Failed to marshal progress %v", err)
+	}
+	var legacyDec legacyProgress
+	if err := json.Unmarshal(blob, &legacyDec); err != nil {
+		t.Fatalf("Failed to unmarshal progress %v", err)
+	}
+	if !compareProgress(legacyDec, progress) {
+		t.Fatal("sync progress is not forward compatible")
+	}
+}