Enhanced SSDs (ESSDs) that support the Non-Volatile Memory Express (NVMe) protocol are called NVMe disks. NVMe disks can be simultaneously attached to multiple Elastic Compute Service (ECS) instances that support NVMe for data sharing. This topic describes the limits of NVMe disks and related operations.
Overview
NVMe disks support concurrent read and write access from multiple ECS instances and provide high reliability, concurrency, and performance. ECS provides the multi-attach and I/O blocking features for NVMe disks. After NVMe disks are attached to Linux instances based on NVMe, you can run the lsblk command to check the device names and partition names of the NVMe disks, as shown in the following figure.
The following items describe the device names and partition names of NVMe disks:
The device names of NVMe disks are displayed in the
/dev/nvmeXn1format. Examples: /dev/nvme0n1, /dev/nvme1n1, and /dev/nvme2n1.The partition names of NVMe disks are displayed in the
<Device name>p<Partition number>format. Examples: /dev/nvme0n1p1, /dev/nvme1n1p1, and /dev/nvme1n1p2.
The multi-attach feature allows you to attach a single NVMe disk to up to 16 ECS instances that support the NVMe protocol at the same time. For information about how to enable the multi-attach feature for NVMe disks, see Enable multi-attach.
Limits
Before you attach NVMe disks to an ECS instance based on NVMe, make sure that the resources of the instance meet the conditions described in the following table.
Resource | Description |
Region and zone | The region and zone must be the same as the region and zone supported by the corresponding instance family. |
Instance family | The instance family must support NVMe by default. The following instance families support the multi-attach feature: g7se, c7se, r7se, c8y, g8y, r8y, g8ae, c8ae, r8ae, g8i, c8i, and r8i. For more information, see Overview of instance families. Note You can call the DescribeInstanceTypes operation to query instance families and check the NvmeSupport response parameter to determine whether an instance family supports NVMe. |
Image | The image must contain the NVMe driver. The NVMe driver is pre-installed in the following public images. Note Only specific Linux and Windows public images support the NVMe driver.
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Disk |
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Billing
NVMe is provided free of charge. You are charged for resources that support NVMe based on their individual billing methods. For information about the billing of ECS resources, see Billing overview.
Operations
The following table describes the operations that you can perform on NVMe disks.
Operation | Description | References |
Create an ECS instance that supports NVMe | When you create an ECS instance that supports NVMe, you can create ESSDs along with the instance. These ESSDs are NVMe disks. | |
Enable the multi-attach feature for an NVMe disk | When you separately create an ESSD, you can enable the multi-attach feature and attach the ESSD to multiple ECS instances that support NVMe. | |
Initialize an NVMe disk | NVMe disks created along with instances can be initialized. Important This operation is applicable only to ESSDs that are created along with instances. |
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Resize an NVMe disk | If the disk space of an NVMe disk is insufficient, you can resize the disk online to extend its capacity. |