Using exponential backoff instead of linear

Author: edisonxiang

pkg/volume/cinder/attacher.go

@@ -44,7 +44,9 @@ var _ volume.Attacher = &cinderDiskAttacher{}
 var _ volume.AttachableVolumePlugin = &cinderPlugin{}
 
 const (
-	checkSleepDuration       = 5 * time.Second
+	probeVolumeInitDealy     = 1 * time.Second
+	probeVolumeFactor        = 2.0
+	probeVolumeSteps         = 10
 	operationFinishInitDealy = 1 * time.Second
 	operationFinishFactor    = 1.1
 	operationFinishSteps     = 10
@@ -221,6 +223,38 @@ func (attacher *cinderDiskAttacher) VolumesAreAttached(specs []*volume.Spec, nod
 	return volumesAttachedCheck, nil
 }
 
+func (attacher *cinderDiskAttacher) waitProbeVolume(devicePath, volumeID string) (string, error) {
+	backoff := wait.Backoff{
+		Duration: probeVolumeInitDealy,
+		Factor:   probeVolumeFactor,
+		Steps:    probeVolumeSteps,
+	}
+
+	err := wait.ExponentialBackoff(backoff, func() (string, error) {
+		glog.V(5).Infof("Checking Cinder disk %q is attached.", volumeID)
+		probeAttachedVolume()
+		if !attacher.cinderProvider.ShouldTrustDevicePath() {
+			// Using the Cinder volume ID, find the real device path (See Issue #33128)
+			devicePath = attacher.cinderProvider.GetDevicePath(volumeID)
+		}
+		exists, err := volumeutil.PathExists(devicePath)
+		if exists && err == nil {
+			glog.Infof("Successfully found attached Cinder disk %q at %v.", volumeID, devicePath)
+			return devicePath, nil
+		}
+		else {
+			// Log an error, and continue checking periodically
+			glog.Errorf("Error: could not find attached Cinder disk %q (path: %q): %v", volumeID, devicePath, err)
+		}
+	})
+
+	if err == wait.ErrWaitTimeout {
+		err = fmt.Errorf("Volume %q failed to be probed within the alloted time", volumeID)
+	}
+
+	return "", err
+}
+
 func (attacher *cinderDiskAttacher) WaitForAttach(spec *volume.Spec, devicePath string, _ *v1.Pod, timeout time.Duration) (string, error) {
 	// NOTE: devicePath is is path as reported by Cinder, which may be incorrect and should not be used. See Issue #33128
 	volumeSource, _, err := getVolumeSource(spec)
@@ -234,32 +268,8 @@ func (attacher *cinderDiskAttacher) WaitForAttach(spec *volume.Spec, devicePath
 		return "", fmt.Errorf("WaitForAttach failed for Cinder disk %q: devicePath is empty.", volumeID)
 	}
 
-	ticker := time.NewTicker(checkSleepDuration)
-	defer ticker.Stop()
-	timer := time.NewTimer(timeout)
-	defer timer.Stop()
-
-	for {
-		select {
-		case <-ticker.C:
-			glog.V(5).Infof("Checking Cinder disk %q is attached.", volumeID)
-			probeAttachedVolume()
-			if !attacher.cinderProvider.ShouldTrustDevicePath() {
-				// Using the Cinder volume ID, find the real device path (See Issue #33128)
-				devicePath = attacher.cinderProvider.GetDevicePath(volumeID)
-			}
-			exists, err := volumeutil.PathExists(devicePath)
-			if exists && err == nil {
-				glog.Infof("Successfully found attached Cinder disk %q at %v.", volumeID, devicePath)
-				return devicePath, nil
-			} else {
-				// Log an error, and continue checking periodically
-				glog.Errorf("Error: could not find attached Cinder disk %q (path: %q): %v", volumeID, devicePath, err)
-			}
-		case <-timer.C:
-			return "", fmt.Errorf("Could not find attached Cinder disk %q. Timeout waiting for mount paths to be created.", volumeID)
-		}
-	}
+	// Using exponential backoff instead of linear
+	return attacher.waitProbeVolume(devicePath, volumeID)
 }
 
 func (attacher *cinderDiskAttacher) GetDeviceMountPath(

pkg/volume/cinder/cinder_util.go

@@ -228,12 +228,11 @@ func probeAttachedVolume() error {
 	// udevadm settle waits for udevd to process the device creation
 	// events for all hardware devices, thus ensuring that any device
 	// nodes have been created successfully before proceeding.
-	argsSettle := []string{"settle", "--timeout=1"}
+	argsSettle := []string{"settle"}
 	cmdSettle := executor.Command("udevadm", argsSettle...)
 	_, errSettle := cmdSettle.CombinedOutput()
 	if errSettle != nil {
 		glog.Errorf("error running udevadm settle %v\n", errSettle)
-		return errSettle
 	}
 
 	args := []string{"trigger"}