cmd/utils, eth/ethconfig: unindex txs older than ~1 year

cmd/utils/flags.go

@@ -212,10 +212,10 @@ var (
 		Name:  "snapshot",
 		Usage: `Enables snapshot-database mode (default = enable)`,
 	}
-	TxLookupLimitFlag = cli.Int64Flag{
+	TxLookupLimitFlag = cli.Uint64Flag{
 		Name:  "txlookuplimit",
-		Usage: "Number of recent blocks to maintain transactions index by-hash for (default = index all blocks)",
-		Value: 0,
+		Usage: "Number of recent blocks to maintain transactions index for (default = about one year, 0 = entire chain)",
+		Value: ethconfig.Defaults.TxLookupLimit,
 	}
 	LightKDFFlag = cli.BoolFlag{
 		Name:  "lightkdf",

eth/ethconfig/config.go

@@ -66,6 +66,7 @@ var Defaults = Config{
 		DatasetsLockMmap: false,
 	},
 	NetworkId:               1,
+	TxLookupLimit:           2350000,
 	LightPeers:              100,
 	UltraLightFraction:      75,
 	DatabaseCache:           512,