feat(loadgen): add burst subcommand and make scheduled bursts opt-in

Default burst-per-day changed from 2 to 0 so the start command
no longer fires bursts unless explicitly configured. New burst
subcommand triggers a single burst workload immediately, reusing
the same matrix execution path as the scheduler.

Author: chatton

apps/loadgen/cmd/burst.go

@@ -0,0 +1,37 @@
+package cmd
+
+import (
+	"log"
+
+	"github.com/evstack/ev-node/apps/loadgen/internal"
+	"github.com/spf13/cobra"
+)
+
+func newBurstCmd() *cobra.Command {
+	var (
+		txCount    int
+		matrixPath string
+	)
+
+	cmd := &cobra.Command{
+		Use:   "burst",
+		Short: "trigger a single burst workload immediately",
+		Args:  cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			spamoorAddr := resolveSpamoorURL()
+			api := internal.NewSpamoorClient(spamoorAddr)
+
+			if err := internal.WaitForSync(cmd.Context(), api); err != nil {
+				return err
+			}
+
+			log.Printf("==> burst workload starting (%d tx)", txCount)
+			return internal.ExecuteMatrixWithOverridesFromFile(cmd.Context(), matrixPath, api, txCount)
+		},
+	}
+
+	cmd.Flags().IntVar(&txCount, "tx-count", envIntOr("BENCH_BURST_TX_COUNT", 500000), "total transactions for the burst")
+	cmd.Flags().StringVar(&matrixPath, "burst-matrix", envStringOr("BENCH_BURST_MATRIX", defaultBurstPath), "path to burst matrix JSON")
+
+	return cmd
+}

apps/loadgen/cmd/root.go

@@ -16,7 +16,7 @@ func NewRootCmd() *cobra.Command {
 
 	rootCmd.PersistentFlags().StringVar(&spamoorFlag, "spamoor-url", "", "spamoor-daemon API URL (env: BENCH_SPAMOOR_URL)")
 
-	rootCmd.AddCommand(newRunCmd(), newStartCmd(), newCheckCmd())
+	rootCmd.AddCommand(newRunCmd(), newStartCmd(), newCheckCmd(), newBurstCmd())
 
 	return rootCmd
 }

apps/loadgen/cmd/start.go

@@ -46,7 +46,7 @@ func newStartCmd() *cobra.Command {
 	cmd.Flags().IntVar(&cfg.txPerDay, "tx-per-day", envIntOr("BENCH_TX_PER_DAY", 1000000), "sustained txs/day")
 	cmd.Flags().DurationVar(&cfg.interval, "interval", envDurationOr("BENCH_INTERVAL", time.Hour), "regular workload frequency")
 	cmd.Flags().IntVar(&cfg.burstTxCount, "burst-tx-count", envIntOr("BENCH_BURST_TX_COUNT", 500000), "txs per burst")
-	cmd.Flags().IntVar(&cfg.burstPerDay, "burst-per-day", envIntOr("BENCH_BURST_PER_DAY", 2), "bursts per day, randomly spaced")
+	cmd.Flags().IntVar(&cfg.burstPerDay, "burst-per-day", envIntOr("BENCH_BURST_PER_DAY", 0), "bursts per day, randomly spaced (0 = no bursts)")
 	cmd.Flags().StringVar(&cfg.regularMatrix, "regular-matrix", envStringOr("BENCH_REGULAR_MATRIX", defaultBaselinePath), "path to regular matrix JSON")
 	cmd.Flags().StringVar(&cfg.burstMatrix, "burst-matrix", envStringOr("BENCH_BURST_MATRIX", defaultBurstPath), "path to burst matrix JSON")