chore: x/genutil: cleanup CollectTxs

This change moves []os.DirEntry close to where it is used
and also reuses the already created sdk.AccAddress.String()
[]byte->string (sure it is cached but unnecessary to re-invoke)
as a key to the balancesMap.

Fixes #17814

x/genutil/collect.go

@@ -76,12 +76,6 @@ func CollectTxs(cdc codec.JSONCodec, txJSONDecoder sdk.TxDecoder, moniker, genTx
 		return appGenTxs, persistentPeers, err
 	}
 
-	var fos []os.DirEntry
-	fos, err = os.ReadDir(genTxsDir)
-	if err != nil {
-		return appGenTxs, persistentPeers, err
-	}
-
 	balancesMap := make(map[string]bankexported.GenesisBalance)
 
 	genBalIterator.IterateGenesisBalances(
@@ -93,9 +87,17 @@ func CollectTxs(cdc codec.JSONCodec, txJSONDecoder sdk.TxDecoder, moniker, genTx
 		},
 	)
 
+	fos, err := os.ReadDir(genTxsDir)
+	if err != nil {
+		return appGenTxs, persistentPeers, err
+	}
+
 	// addresses and IPs (and port) validator server info
 	var addressesIPs []string
 
+	// TODO (https://github.com/cosmos/cosmos-sdk/issues/17815):
+	// Examine CPU and RAM profiles to see if we can parsing
+	// and ValidateAndGetGenTx concurrent.
 	for _, fo := range fos {
 		if fo.IsDir() {
 			continue
@@ -151,7 +153,7 @@ func CollectTxs(cdc codec.JSONCodec, txJSONDecoder sdk.TxDecoder, moniker, genTx
 			return appGenTxs, persistentPeers, fmt.Errorf("account %s balance not in genesis state: %+v", valAccAddr, balancesMap)
 		}
 
-		_, valOk := balancesMap[sdk.AccAddress(valAddr).String()]
+		_, valOk := balancesMap[valAccAddr]
 		if !valOk {
 			_, file, no, ok := runtime.Caller(1)
 			if ok {