fix: broadcast to all rendezvous at once when spawn done

Change-Id: Ic04bc2f56aa40c2af42a1fdb3c261a10e8346033

internal/boomer/boomer.go

@@ -128,8 +128,8 @@ func (b *Boomer) Quit() {
 	b.localRunner.stop()
 }
 
-func (b *Boomer) IsSpawnDone() bool {
-	return b.localRunner.isSpawnDone
+func (b *Boomer) GetSpawnDoneChan() chan struct{} {
+	return b.localRunner.spawnDone
 }
 
 func (b *Boomer) GetSpawnCount() int {

internal/boomer/runner.go

@@ -63,7 +63,7 @@ type runner struct {
 	spawnCount        int   // target clients to spawn
 	spawnRate         float64
 	loop              *Loop // specify running cycles
-	isSpawnDone       bool
+	spawnDone         chan struct{}
 
 	outputs []Output
 }
@@ -194,7 +194,7 @@ func (r *localRunner) spawnWorkers(spawnCount int, spawnRate float64, quit chan
 		}
 	}
 
-	r.isSpawnDone = true
+	close(r.spawnDone)
 	if spawnCompleteFunc != nil {
 		spawnCompleteFunc()
 	}
@@ -256,6 +256,7 @@ func newLocalRunner(spawnCount int, spawnRate float64) *localRunner {
 			spawnCount: spawnCount,
 			stats:      newRequestStats(),
 			outputs:    make([]Output, 0),
+			spawnDone:  make(chan struct{}),
 		},
 		stopChan: make(chan bool),
 	}