This topic provides general information about Alibaba Cloud enhanced SSDs (ESSDs), such as performance levels, use scenarios, and performance specifications. ESSDs are provisioned on a 25 GE network and remote direct memory access (RDMA) technology. They deliver a maximum random IOPS of 1 million per disk and low one-way latency.

Scenarios

ESSDs feature low latency, fast response, and high data throughput. They are ideal for latency-sensitive applications or I/O-intensive business scenarios. For example:

  • Online transaction processing (OLTP) databases: relational databases, such as MySQL, PostgreSQL, Oracle, and SQL Server databases.
  • NoSQL databases: non-relational databases, such as MongoDB, HBase, and Cassandra databases.
  • Real-time analysis applications: Elasticsearch distributed log analysis, Elasticsearch, Logstash, and Kibana (ELK) log analysis.

Specifications

The API parameter value of ESSDs is cloud_essd. ESSDs are divided into three performance levels (PLs) based on the maximum performance per disk.

ESSD attribute Performance level 3 Performance level 2 Performance level 1
Performance level PL3 PL2 PL1
Performance description Ultra high concurrent I/O performance and ultra low I/O latency High concurrent I/O performance and low I/O latency Moderate concurrent I/O performance and low I/O latency
Capacity (GiB) 1,261-32,768 461-32,768 20-32,768
Data reliability 99.9999999% 99.9999999% 99.9999999%
Maximum IOPS per disk 1,000,000 100,000 50,000
Maximum throughput per disk (MB/s) 4,000 750 350
Calculate disk IOPS Min{1800 + 50 × Capacity, 1000000} Min{1800 + 50 × Capacity, 100000} Min{1800 + 50 × Capacity, 50000}
Calculate disk throughput (MB/s) Min{120 + 0.5 × Capacity, 4000} Min{120 + 0.5 × Capacity, 750} Min{120 + 0.5 × Capacity, 350}
Applicable to the following products Instance families with local SSDs and 16 or more vCPUs (i1, i2, and i2g) SSDs and instance families with local SSDs (i1, i2, and i2g) Standard SSDs and ultra disks
Scenario example Large and medium-sized relational databases for core businesses and NoSQL databases, and large SAP and Oracle databases Medium-sized relational databases, NoSQL databases, medium-sized ELK log clusters, and enterprise-grade commercial software such as SAP and Oracle Small and medium-sized MySQL and SQL Server databases, small and medium-sized ELK log clusters, enterprise-grade commercial software such as SAP and Oracle, and container applications

Billing

ESSDs support pay-as-you-go and subscription billing methods. For more information, see Create a pay-as-you-go disk and Create a subscription disk.

For information about the pricing for different ESSD performance levels, click the Pricing tab of the Elastic Compute Service page.

ESSD capacity and performance levels

The performance of a storage device is closely related to the capacity of the device. A storage device with larger capacity provides more powerful data processing capabilities. All ESSDs have the same I/O performance per unit capacity. However, the performance of ESSDs increases linearly with its capacity until the maximum performance per disk for that performance level is reached.
Performance level ESSD capacity (GiB) Maximum IOPS Maximum throughput (MB/s)
PL1 20-32,768 50,000 350
PL2 461-32,768 100,000 750
PL3 1,261-32,768 1,000,000 4,000
  • Example 1: If Alex selects 20 GiB memory when he creates an ESSD in the ECS console, PL1 is the only available option. PL1 ESSDs have a maximum IOPS of 50,000.
  • Example 2: If Alex selects 32,000 GiB memory, all performance levels are available. The maximum IOPS for PL1 is 50,000, PL2 is 100,000, and PL3 is 1,000,000.

Storage I/O performance of instance types

The storage I/O performance of some new-generation instance families is proportional to the specifications of the instance types.

The following examples show you how instance types affect the maximum IOPS and throughput of an ESSD.

  • Example 1: Alex creates a 16 GiB instance of the ecs.g5se.xlarge instance type. The maximum IOPS of this instance type is 60,000. Alex then attaches an ESSD whose capacity is 1,800 GiB and the maximum IOPS is 100,000 to the instance. The maximum IOPS of the instance is 60,000, because it is limited by the maximum IOPS of the instance type.
  • Example 2: Alex creates a 64 GiB instance of the ecs.g5se.4xlarge instance type. The maximum IOPS of this instance type is 230,000. Alex then attaches an ESSD whose capacity is 1,800 GiB and the maximum IOPS is 100,000 to the instance. The maximum IOPS of the instance is 100,000, because it is no longer limited by the maximum IOPS of the instance type, but is instead limited by the maximum IOPS of the ESSD.

Related operations

Business need Reference API operation
Create an ESSD separately and use it as a data disk CreateDisk
Change billing methods Convert the billing method of a cloud disk ModifyDiskChargeType
Attach a pay-as-you-go data disk to an ECS instance Attach a data disk AttachDisk
Create a normal or local snapshot Create a normal snapshot CreateSnapshot
Increase the capacity of an ESSD Overview ResizeDisk
Resize an ESSD to improve performance
Detach a pay-as-you-go data disk Detach a data disk DetachDisk
Release a data disk Release a disk DeleteDisk