optimize: extended expire time for sequencer block broadcasting (ethe…

…reum-optimism#106)

* config: change block validator payload from 60s to 20 min

* config: increase seenMessagesTTL AND blockHeightLRU to avoid old block validation

op-node/p2p/gossip.go

@@ -34,8 +34,8 @@ const (
 	globalValidateThrottle = 512
 	gossipHeartbeat        = 500 * time.Millisecond
 	// seenMessagesTTL limits the duration that message IDs are remembered for gossip deduplication purposes
-	// 130 * gossipHeartbeat
-	seenMessagesTTL  = 130 * gossipHeartbeat
+	// 2500 * gossipHeartbeat
+	seenMessagesTTL  = 2500 * gossipHeartbeat
 	DefaultMeshD     = 8  // topic stable mesh target count
 	DefaultMeshDlo   = 6  // topic stable mesh low watermark
 	DefaultMeshDhi   = 12 // topic stable mesh high watermark
@@ -242,7 +242,7 @@ func BuildBlocksValidator(log log.Logger, cfg *rollup.Config, runCfg GossipRunti
 
 	// Seen block hashes per block height
 	// uint64 -> *seenBlocks
-	blockHeightLRU, err := lru.New(1000)
+	blockHeightLRU, err := lru.New(1500)
 	if err != nil {
 		panic(fmt.Errorf("failed to set up block height LRU cache: %w", err))
 	}
@@ -291,8 +291,8 @@ func BuildBlocksValidator(log log.Logger, cfg *rollup.Config, runCfg GossipRunti
 		// rounding down to seconds is fine here.
 		now := uint64(time.Now().Unix())
 
-		// [REJECT] if the `payload.timestamp` is older than 60 seconds in the past
-		if uint64(payload.Timestamp) < now-60 {
+		// [REJECT] if the `payload.timestamp` is older than 20 min in the past
+		if uint64(payload.Timestamp) < now-1200 {
 			log.Warn("payload is too old", "timestamp", uint64(payload.Timestamp))
 			return pubsub.ValidationReject
 		}