polygon: keep devp2p max peers default to 100 as before (#13361)

Follow up after #13003 changed
default devp2p peers from 100 to 32
Keep the previous default of 100 pers for polygon since the
recommendation for it is to keep a higher peer count as per recent
changes to their peering strategy -
https://forum.polygon.technology/t/introducing-our-new-dns-discovery-for-polygon-pos-faster-smarter-more-connected/19871

cmd/utils/flags.go

@@ -1420,8 +1420,7 @@ func SetP2PConfig(ctx *cli.Context, cfg *p2p.Config, nodeName, datadir string, l
 		cfg.MetricsEnabled = ctx.Bool(MetricsEnabledFlag.Name)
 	}
 
-	ethPeers := cfg.MaxPeers
-	logger.Info("Maximum peer count", "ETH", ethPeers, "total", cfg.MaxPeers)
+	logger.Info("Maximum peer count", "total", cfg.MaxPeers)
 
 	if netrestrict := ctx.String(NetrestrictFlag.Name); netrestrict != "" {
 		list, err := netutil.ParseNetlist(netrestrict)
@@ -1679,15 +1678,23 @@ func setClique(ctx *cli.Context, cfg *params.ConsensusSnapshotConfig, datadir st
 	}
 }
 
-func setBorConfig(ctx *cli.Context, cfg *ethconfig.Config) {
+func setBorConfig(ctx *cli.Context, cfg *ethconfig.Config, nodeConfig *nodecfg.Config, logger log.Logger) {
 	cfg.HeimdallURL = ctx.String(HeimdallURLFlag.Name)
 	cfg.WithoutHeimdall = ctx.Bool(WithoutHeimdallFlag.Name)
 	cfg.WithHeimdallMilestones = ctx.Bool(WithHeimdallMilestones.Name)
 	cfg.WithHeimdallWaypointRecording = ctx.Bool(WithHeimdallWaypoints.Name)
 	cfg.PolygonSync = ctx.Bool(PolygonSyncFlag.Name)
 	cfg.PolygonSyncStage = ctx.Bool(PolygonSyncStageFlag.Name)
-	heimdall.RecordWayPoints(
-		cfg.WithHeimdallWaypointRecording || cfg.PolygonSync || cfg.PolygonSyncStage)
+	heimdall.RecordWayPoints(cfg.WithHeimdallWaypointRecording || cfg.PolygonSync || cfg.PolygonSyncStage)
+
+	chainConfig := params.ChainConfigByChainName(ctx.String(ChainFlag.Name))
+	if chainConfig.Bor != nil && !ctx.IsSet(MaxPeersFlag.Name) {
+		// override default max devp2p peers for polygon as per
+		// https://forum.polygon.technology/t/introducing-our-new-dns-discovery-for-polygon-pos-faster-smarter-more-connected/19871
+		// which encourages high peer count
+		nodeConfig.P2P.MaxPeers = 100
+		logger.Info("Maximum peer count default sanitizing for bor", "total", nodeConfig.P2P.MaxPeers)
+	}
 }
 
 func setMiner(ctx *cli.Context, cfg *params.MiningConfig) {
@@ -1928,7 +1935,7 @@ func SetEthConfig(ctx *cli.Context, nodeConfig *nodecfg.Config, cfg *ethconfig.C
 	setClique(ctx, &cfg.Clique, nodeConfig.Dirs.DataDir)
 	setMiner(ctx, &cfg.Miner)
 	setWhitelist(ctx, cfg)
-	setBorConfig(ctx, cfg)
+	setBorConfig(ctx, cfg, nodeConfig, logger)
 	setSilkworm(ctx, cfg)
 	if err := setBeaconAPI(ctx, cfg); err != nil {
 		log.Error("Failed to set beacon API", "err", err)