Add target gas param

Author: udpatil

config/settings.go

@@ -25,6 +25,7 @@ type Settings struct {
 	RampUp           bool     `json:"rampUp,omitempty"`
 	ReportPath       string   `json:"reportPath,omitempty"`
 	TxsDir           string   `json:"txsDir,omitempty"`
+	TargetGas        uint64   `json:"targetGas,omitempty"`
 }
 
 // DefaultSettings returns the default configuration values
@@ -43,6 +44,7 @@ func DefaultSettings() Settings {
 		RampUp:           false,
 		ReportPath:       "",
 		TxsDir:           "",
+		TargetGas:        10_000_000,
 	}
 }
 
@@ -63,6 +65,7 @@ func InitializeViper(cmd *cobra.Command) error {
 		"rampUp":           "ramp-up",
 		"reportPath":       "report-path",
 		"txsDir":           "txs-dir",
+		"targetGas":        "target-gas",
 	}
 
 	for viperKey, flagName := range flagBindings {
@@ -86,6 +89,7 @@ func InitializeViper(cmd *cobra.Command) error {
 	viper.SetDefault("rampUp", defaults.RampUp)
 	viper.SetDefault("reportPath", defaults.ReportPath)
 	viper.SetDefault("txsDir", defaults.TxsDir)
+	viper.SetDefault("targetGas", defaults.TargetGas)
 	return nil
 }
 
@@ -125,5 +129,6 @@ func ResolveSettings() Settings {
 		RampUp:           viper.GetBool("rampUp"),
 		ReportPath:       viper.GetString("reportPath"),
 		TxsDir:           viper.GetString("txsDir"),
+		TargetGas:        viper.GetUint64("targetGas"),
 	}
 }

main.go

@@ -12,6 +12,7 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/ethereum/go-ethereum/ethclient"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/spf13/cobra"
 	"go.opentelemetry.io/otel"
@@ -66,6 +67,7 @@ func init() {
 	rootCmd.Flags().Bool("ramp-up", false, "Ramp up loadtest")
 	rootCmd.Flags().String("report-path", "", "Path to save the report")
 	rootCmd.Flags().String("txs-dir", "", "Path to save the transactions")
+	rootCmd.Flags().Uint64("target-gas", 10_000_000, "Target gas per block")
 
 	// Initialize Viper with proper error handling
 	if err := config.InitializeViper(rootCmd); err != nil {
@@ -228,7 +230,18 @@ func runLoadTest(ctx context.Context, cmd *cobra.Command, args []string) error {
 		// Create dispatcher
 		var dispatcher *sender.Dispatcher
 		if settings.TxsDir != "" {
-			writer := sender.NewTxsWriter(10_000_000, settings.TxsDir)
+			// get latest height
+			ethclient, err := ethclient.Dial(cfg.Endpoints[0])
+			if err != nil {
+				return fmt.Errorf("failed to create ethclient: %w", err)
+			}
+			latestHeight, err := ethclient.BlockNumber(ctx)
+			if err != nil {
+				return fmt.Errorf("failed to get latest height: %w", err)
+			}
+			writerHeight := latestHeight + 10 // some buffer
+			log.Printf("🔍 Latest height: %d, writer start height: %d", latestHeight, writerHeight)
+			writer := sender.NewTxsWriter(settings.TargetGas, settings.TxsDir, writerHeight, 100)
 			dispatcher = sender.NewDispatcher(gen, writer)
 		} else {
 			dispatcher = sender.NewDispatcher(gen, snd)

sender/writer.go

@@ -14,20 +14,24 @@ import (
 // implements `Send`
 
 type TxsWriter struct {
-	gasPerBlock uint64
-	nextHeight  uint64
-	txsDir      string
+	gasPerBlock     uint64
+	nextHeight      uint64
+	txsDir          string
+	blocksGenerated uint64
+	numBlocks       uint64
 
 	bufferGas uint64
 	txBuffer  []*types.LoadTx
 }
 
-func NewTxsWriter(gasPerBlock uint64, txsDir string) *TxsWriter {
+func NewTxsWriter(gasPerBlock uint64, txsDir string, startHeight uint64, numBlocks uint64) *TxsWriter {
 	// what height to start at?
 	return &TxsWriter{
-		gasPerBlock: gasPerBlock,
-		nextHeight:  1,
-		txsDir:      txsDir,
+		gasPerBlock:     gasPerBlock,
+		nextHeight:      startHeight,
+		txsDir:          txsDir,
+		blocksGenerated: 0,
+		numBlocks:       numBlocks,
 
 		bufferGas: 0,
 		txBuffer:  make([]*types.LoadTx, 0),
@@ -59,6 +63,7 @@ func (w *TxsWriter) Flush() error {
 		w.txBuffer = make([]*types.LoadTx, 0)
 		w.bufferGas = 0
 		w.nextHeight++
+		w.blocksGenerated++
 	}()
 	// write to dir `~/load_txs`
 	// make dir if it doesn't exist
@@ -82,5 +87,9 @@ func (w *TxsWriter) Flush() error {
 
 	log.Printf("Flushed %d transactions to %s", len(w.txBuffer), txsFile)
 
+	if w.blocksGenerated >= w.numBlocks {
+		return fmt.Errorf("reached max number of blocks: %d", w.numBlocks)
+	}
+
 	return nil
 }

sender/writer_test.go

@@ -13,7 +13,7 @@ import (
 
 func TestTxsWriter_Flush(t *testing.T) {
 	// two evm transfer txs
-	writer := NewTxsWriter(42000, "/tmp")
+	writer := NewTxsWriter(42000, "/tmp", 1)
 
 	loadConfig := &config.LoadConfig{
 		ChainID: 7777,