Amazon EBS and NVMe on Windows instances

EBS volumes are exposed as NVMe block devices on instances built on the Nitro System. When you attach a volume to your instance, you include a device name for the volume. This device name is used by Amazon EC2. The block device driver for the instance assigns the actual volume name when mounting the volume, and the name assigned can be different from the name that Amazon EC2 uses.

The EBS performance guarantees stated in Amazon EBS Product Details are valid regardless of the block-device interface.

Install or upgrade the NVMe driver

The AWS Windows AMIs for Windows Server 2008 R2 and later include the AWS NVMe driver. If you are not using the latest AWS Windows AMIs provided by Amazon, see Install or upgrade AWS NVMe drivers.

Identify the EBS device

EBS uses single-root I/O virtualization (SR-IOV) to provide volume attachments on Nitro-based instances using the NVMe specification. These devices rely on standard NVMe drivers on the operating system. These drivers typically discover attached devices by scanning the PCI bus during instance boot, and create device nodes based on the order in which the devices respond, not on how the devices are specified in the block device mapping. Additionally, the device name assigned by the block device driver can be different from the name specified in the block device mapping.

The following example shows the command and output for a volume attached during instance launch. Note that the NVMe device name does not include the /dev/ prefix.

The following example shows the command and output for a volume attached after instance launch. Note that the NVMe device name includes the /dev/ prefix.

Windows Server 2008 R2 and later

You can also run the ebsnvme-id command to map the NVMe device disk number to an EBS volume ID and device name. By default, all EBS NVMe devices are enumerated. You can pass a disk number to enumerate information for a specific device. Ebsnvme-id is included in the latest AWS provided Windows Server AMIs located in C:\PROGRAMDATA\AMAZON\Tools.

You can also download ebsnvme-id.zip and extract the contents to your Amazon EC2 instance to get access to ebsnvme-id.exe.

PS C:\Users\Administrator\Desktop> ebsnvme-id.exe
Disk Number: 0
Volume ID: vol-0d6d7ee9f6e471a7f
Device Name: sda1

Disk Number: 1
Volume ID: vol-03a26248ff39b57cf
Device Name: xvdd

Disk Number: 2
Volume ID: vol-038bd1c629aa125e6
Device Name: xvde

Disk Number: 3
Volume ID: vol-034f9d29ec0b64c89
Device Name: xvdb

Disk Number: 4
Volume ID: vol-03e2dbe464b66f0a1
Device Name: xvdc
PS C:\Users\Administrator\Desktop> ebsnvme-id.exe 4
Disk Number: 4
Volume ID: vol-03e2dbe464b66f0a1
Device Name: xvdc

Work with NVMe EBS volumes

The latest AWS Windows AMIs contain the AWS NVMe driver that is required by instance types that expose EBS volumes as NVMe block devices. However, if you resize your root volume on a Windows system, you must rescan the volume in order for this change to be reflected in the instance. If you launched your instance from a different AMI, it might not contain the required AWS NVMe driver. If your instance does not have the latest AWS NVMe driver, you must install it. For more information, see AWS NVMe drivers for Windows instances.

I/O operation timeout

Most operating systems specify a timeout for I/O operations submitted to NVMe devices. On Windows systems, the default timeout is 60 seconds and the maximum is 255 seconds. You can modify the TimeoutValue disk class registry setting using the procedure described in Registry Entries for SCSI Miniport Drivers.