Fix Go mistake findings and stabilize integration timing

1 files changed, 20 insertions, 3 deletions

diff --git a/integrationtests/harness.go b/integrationtests/harness.go
index a8a73d0..17ae994 100644
--- a/integrationtests/harness.go
+++ b/integrationtests/harness.go
@@ -102,6 +102,9 @@ func (h *TestHarness) startWorkload(scenario string) (*exec.Cmd, int, error) {
 		io.Copy(io.Discard, stdout) //nolint:errcheck
 	}()
 
+	startupTimer := time.NewTimer(workloadStartupTimeout)
+	defer stopAndDrainTimer(startupTimer)
+
 	select {
 	case pid := <-pidCh:
 		return cmd, pid, nil
@@ -109,7 +112,7 @@ func (h *TestHarness) startWorkload(scenario string) (*exec.Cmd, int, error) {
 		cmd.Process.Kill()
 		cmd.Wait()
 		return nil, 0, err
-	case <-time.After(workloadStartupTimeout):
+	case <-startupTimer.C:
 		cmd.Process.Kill()
 		cmd.Wait()
 		return nil, 0, fmt.Errorf("timeout waiting for workload PID")
@@ -151,7 +154,8 @@ func waitBoth(workloadCmd, iorCmd *exec.Cmd, duration int, grace time.Duration)
 	go func(ch chan error) { ch <- workloadCmd.Wait() }(workloadDone)
 	go func(ch chan error) { ch <- iorCmd.Wait() }(iorDone)
 
-	timeout := time.After(time.Duration(duration)*time.Second + grace)
+	timeout := time.NewTimer(time.Duration(duration)*time.Second + grace)
+	defer stopAndDrainTimer(timeout)
 
 	for workloadDone != nil || iorDone != nil {
 		select {
@@ -161,7 +165,7 @@ func waitBoth(workloadCmd, iorCmd *exec.Cmd, duration int, grace time.Duration)
 		case err := <-iorDone:
 			iorErr = err
 			iorDone = nil
-		case <-timeout:
+		case <-timeout.C:
 			if iorDone != nil {
 				iorCmd.Process.Kill()
 				iorErr = fmt.Errorf("ior timed out")
@@ -178,6 +182,19 @@ func waitBoth(workloadCmd, iorCmd *exec.Cmd, duration int, grace time.Duration)
 	return
 }
 
+func stopAndDrainTimer(timer *time.Timer) {
+	if timer == nil {
+		return
+	}
+	if timer.Stop() {
+		return
+	}
+	select {
+	case <-timer.C:
+	default:
+	}
+}
+
 // findIorZstFile locates the .ior.zst file matching the scenario name in the output directory.
 func findIorZstFile(dir, scenario string) (string, error) {
 	entries, err := os.ReadDir(dir)