v2: set constants and varialbes

cmd/utils/flags.go

@@ -1076,7 +1076,7 @@ var (
 
 	SnapshotKeepAfterPruningFlag = &cli.IntFlag{
 		Name:  "snapshot.keep-after-pruning",
-		Usage: "The number of lastest snapshots to keep after pruning (default 50)",
+		Usage: "The number of lastest snapshots to keep after pruning (default 200 * 144 = 28800 ~ 1 day)",
 		Value: 200 * 144,
 	}
 )

consensus/consortium/v2/snapshot.go

@@ -21,6 +21,17 @@ import (
 	lru "github.com/hashicorp/golang-lru"
 )
 
+const (
+	blocksPerEpoch  = 200
+	epochsPerPeriod = 144
+)
+
+var (
+	latestSnapshotsKeep = blocksPerEpoch * epochsPerPeriod * 5 // 5 days
+	snapshotsToBePruned = epochsPerPeriod * 2                  // 2 days
+	pruningPeriod       = blocksPerEpoch * epochsPerPeriod * 1 // every 1 day
+)
+
 // Snapshot is the state of the authorization validators at a given point in time.
 type Snapshot struct {
 	// private fields are not json.Marshalled
@@ -119,8 +130,8 @@ func (s *Snapshot) pruneSnapshot(db ethdb.Database, nSnapshotPrune int, chain co
 	log.Info("Pruning snapshots at block", "block", s.Number, "nSnapshotPrune", nSnapshotPrune)
 	// Get block number to start pruning
 	curBlockNumber := s.Number
-	curBlockNumber -= curBlockNumber % 200 // make sure the block number is multiple of 200
-	curBlockNumber -= 200 * 144 * 5        // keep the last 5 days of snapshots
+	curBlockNumber -= curBlockNumber % uint64(blocksPerEpoch) // start of the current epoch
+	curBlockNumber -= uint64(latestSnapshotsKeep)             // start of the oldest epoch to keep
 
 	// delete nSnapshotPrune snapshots starting from curBlockNumber to the older ones
 	batch := db.NewBatch()
@@ -135,25 +146,28 @@ func (s *Snapshot) pruneSnapshot(db ethdb.Database, nSnapshotPrune int, chain co
 		if err := batch.Delete(append(rawdb.ConsortiumSnapshotPrefix, curHash[:]...)); err != nil {
 			return err
 		}
-		curBlockNumber -= 200
+		curBlockNumber -= uint64(blocksPerEpoch)
 	}
 	log.Info("Pruned snapshots done")
 	return batch.Write()
 }
 
+func (s *Snapshot) pruneSnapshotPeriodically(db ethdb.Database, chain consensus.ChainHeaderReader) error {
+	if s.Number%uint64(pruningPeriod) == 0 {
+		return s.pruneSnapshot(db, snapshotsToBePruned, chain)
+	}
+	return nil
+}
+
 // store inserts the snapshot into the database.
 func (s *Snapshot) store(db ethdb.Database, chain consensus.ChainHeaderReader) error {
 	blob, err := json.Marshal(s)
 	if err != nil {
 		return err
 	}
-	// prune nSnapshotPrune snapshots every prunePeriod blocks
-	nSnapshotPrune := 144 * 2 // 2 days
-	prunePeriod := 200 * 144  // 1 day
-	if s.Number%uint64(prunePeriod) == 0 {
-		if err := s.pruneSnapshot(db, nSnapshotPrune, chain); err != nil {
-			log.Error("Failed to prune snapshots", "err", err)
-		}
+	err = s.pruneSnapshotPeriodically(db, chain)
+	if err != nil {
+		log.Error("Failed to prune snapshots", "err", err)
 	}
 	return db.Put(append(rawdb.ConsortiumSnapshotPrefix, s.Hash[:]...), blob)
 }