Why is my Amazon EBS volume that I created from a fast snapshot restore-activated snapshot slow?

Resolution

Note: If you receive errors when you run AWS Command Line Interface (AWS CLI) commands, then see Troubleshoot AWS CLI errors. Also, make sure that you're using the most recent AWS CLI version.

An EBS volume that you create from a snapshot that you activated fast snapshot restore on might occasionally perform slowly. When a snapshot is in the optimizing state, fast snapshot restore provides some performance benefit during volume restoration. However, fast snapshot restore provides full performance only when the snapshot is in the enabled state.

For more information, see Considerations.

To troubleshoot your slow Amazon EBS volume, you can use either the AWS CLI or the Amazon Elastic Compute Cloud (Amazon EC2) console.

Confirm that you created the volume with fast snapshot restore

AWS CLI

Run the describe-volumes command:

aws ec2 describe-volumes --volume-id volume_id --output table

Note: Replace volume_id with your volume ID.

Example output:

DescribeVolumes                Volumes    
AvailabilityZone       ap-southeast-2a    
CreateTime             2022-11-17T22:45:42.999000+00:00    
Encrypted              False    
FastRestored           True    
Iops                   100    
MultiAttachEnabled     False    
Size                   8    
SnapshotI              snap-0b0326ebbfd253c95    
State                  available    
VolumeId               vol-0e51d7f8f003ae2a6    
VolumeType             gp2

If the FastRestored attribute is set to True, then you created the volume with fast snapshot restore. If FastRestored isn't listed, then you didn't create the volume with fast snapshot restore.

Amazon EC2 console

Complete the following steps:

1. Open the Amazon EC2 console.
2. In the navigation pane, choose Volumes.
3. Select your EBS volume.
4. On the Details tab, check the Fast snapshot restore attribute.

If the Fast snapshot restore attribute is Yes, then you created the volume with fast snapshot restore. If the Fast snapshot restore attribute is No, then you didn't create the volume with fast snapshot restore.

Confirm that you activated fast snapshot restore on the snapshot

Before you create an EBS volume, you must activate fast snapshot restore on the snapshot in the same Availability Zone as the volume.

AWS CLI

Run the describe-fast-snapshot-restores command:

aws ec2 describe-fast-snapshot-restores --filters "Name=snapshot-id,Values=snap-#############" --output table

Note: Replace snap-############# with your snapshot ID.

Example output:

DescribeFastSnapshotRestores          FastSnapshotRestores    
AvailabilityZone                      ap-southeast-2a    
EnabledTime                           2022-11-17T12:16:06.014000+00:00    
EnablingTime                          2022-11-17T12:15:29.374000+00:00    
OptimizingTime                        2022-11-17T12:15:39.831000+00:00    
OwnerId                               ############  
SnapshotId                            snap-0b0326ebbfd253c95    
State                                 enabled    
StateTransitionReason                 Client.UserInitiated - Lifecycle state transition

If you activated fast snapshot restore, then State is enabled. If the output lists no attributes, then you didn't activate fast snapshot restore on the snapshot. Check the AvailabilityZone attribute to confirm that's the snapshot is in the same Availability Zone as where you created the volume. Also, check the EnabledTime attribute to determine whether you activated fast snapshot restore on the snapshot before you created the volume.

Amazon EC2 console

Complete the following steps:

1. Open the Amazon EC2 console.
2. In the navigation pane, choose Snapshots.
3. Select the snapshot.
4. On the Details tab, check the Fast snapshot restore attribute.

If you activated fast snapshot restore, then you see the Fast snapshot restore value as enabled and the Availability Zone it's activated in. If the Fast snapshot restore value is blank (-), then you didn't activate fast snapshot restore.

Confirm that there are enough volume creation credits

Check the Amazon CloudWatch FastSnapshotRestoreCreditsBalance metric to confirm that you have enough volume creation credits. For example, to create two volumes from a snapshot that's activated with fast snapshot restore, you must have at least two volume creation credits.

Contact AWS Support

If you still can't resolve your volume's slow performance, then contact AWS Support.