To address diverse storage requirements and resource performance limitations, we recommend using RDS PostgreSQL premium performance disk (a new storage type). This article introduces its performance characteristics, application scenarios, and billing methods to help you deploy quickly.
Feature introduction
Premium performance disk is a new storage type supported by RDS PostgreSQL. While maintaining basic compatibility with all features of ESSD, premium performance disk supports I/O performance burst, Buffer Pool Extension (BPE), and data archiving capabilities, providing higher IOPS and QPS performance when storage capacity remains unchanged or I/O pressure is high.
Premium performance disk currently does not support downloading instance backup data from the Backup And Restoration > Backup List > Data Backup tab.
I/O performance burst: If your business fluctuates frequently with multiple peak periods, you can enable the I/O performance burst feature of premium performance disk. This allows the disk to temporarily exceed the maximum IOPS limit, providing higher I/O capabilities during business peaks to meet sudden business demands.
Buffer Pool Extension (BPE): When databases face I/O bottlenecks due to large-scale or frequent data read/write operations, the Buffer Pool Extension (BPE) feature of premium performance disk significantly improves database I/O performance.
Data archiving: Through the data archiving feature, Object Storage Service (OSS) can be used as a storage medium for archiving cold data, significantly reducing storage costs.
Performance characteristics of premium performance disk
I/O performance: Premium performance disk has improved baseline I/O performance that exceeds ESSD PL1 disk, and adds I/O performance burst capability and Buffer Pool Extension (BPE) capability. For more information, see Service notices.
Premium performance disk storage capacity
Original baseline I/O performance
(Same as ESSD PL1 disk)
Improved baseline I/O performance
Improvement
100 GB ≤ Storage capacity < 1,000 GB
I/O bandwidth: 125 MB/s to 350 MB/s
IOPS: 6,800 to 50,000
I/O bandwidth: 225 MB/s to 450 MB/s
IOPS: 13,200 to 56,400
I/O bandwidth: 100 MB/s
IOPS: 6,400
1,000 GB ≤ Storage capacity < 2,000 GB
I/O bandwidth: 350 MB/s
IOPS: 50,000
I/O bandwidth: 500 MB/s
IOPS: 59,600
I/O bandwidth: 150 MB/s
IOPS: 9,600
2,000 GB ≤ Storage capacity < 4,000 GB
I/O bandwidth: 350 MB/s
IOPS: 50,000
I/O bandwidth: 550 MB/s
IOPS: 62,800
I/O bandwidth: 200 MB/s
IOPS: 12,800
4,000 GB ≤ Storage capacity < 16,000 GB
I/O bandwidth: 350 MB/s
IOPS: 50,000
I/O bandwidth: 600 MB/s
IOPS: 66,000
I/O bandwidth: 250 MB/s
IOPS: 16,000
16,000 GB ≤ Storage capacity < 64,000 GB
I/O bandwidth: 350 MB/s
IOPS: 50,000
I/O bandwidth: 700 MB/s
IOPS: 72,400
I/O bandwidth: 350 MB/s
IOPS: 22,400
Specification flexibility: Multiple configuration options are available, supporting both expansion and reduction of disk space (only certain PostgreSQL instances that meet specific conditions support reduction. For more information, see Change configurations).
Backup method: Snapshot backup is supported.
Time required for backup, read-only instance creation, and instance cloning: Only a few seconds are required.
Time required for storage capacity expansion: Online storage capacity expansion is supported. You can expand the storage capacity of an RDS instance within a few seconds.
Impact of storage capacity expansion: No impacts are imposed.
Data durability: General ESSDs support 99.9999999% data reliability and support RDS instances that run RDS Basic Edition to reduce costs.
Limits
Premium performance disk supports storage capacity ranging from 10 GB to 64,000 GB.
Premium performance disk cannot be changed to any other storage type, but ESSD can be changed to premium performance disk. For more information, see Change ESSD to premium performance disk.
Premium performance disk currently does not support downloading instance backup data from the Backup And Restoration > Backup List > Data Backup tab.
Billing details
Premium performance disk fee = RDS storage space fee + I/O performance burst fee + Buffer Pool Extension (BPE) fee + Data archiving fee
The Buffer Pool Extension (BPE) feature is currently free. The storage space fee is charged based on the purchased storage capacity size. The I/O performance burst fee and data archiving fee are charged based on actual usage. For more information, see:
The fee for the storage capacity that you purchase is the same as the fee for a PL1 ESSD.
There is a price difference between ESSD (PL2, PL3) and premium performance disk. The difference is based on the order in the console at the time of change. If the high I/O duration is shorter, premium performance disk is usually more cost-effective.
Purchase premium performance disk
RDS PostgreSQL supports purchasing premium performance disk through the following methods
Existing RDS instances
Existing ESSD instances can be upgraded to premium performance disk.
Prerequisites
The RDS instance uses the pay-as-you-go or subscription billing method.
The RDS instance uses the ESSD storage type, and the storage capacity of the RDS instance is at least 40 GB.
NoteIf your disk instance was created before October 10, 2022 (old architecture instance), you need to upgrade the minor engine version to the latest version before upgrading ESSD to premium performance disk. For more information, see Upgrade the minor engine version.
Impact
When you change ESSD to premium performance disk, the change takes effect immediately without transient connection issues. In most cases, this operation does not affect your workloads. In some cases, the IOPS of the RDS instance may fluctuate. We recommend that you perform this operation during off-peak hours.
Notes
When the storage type of an instance is changed from ESSD to premium performance disk, the change takes effect on all primary and secondary instances (High-availability Edition) or primary instances (Basic Edition) of the instance. However, the change does not take effect on the read-only instances of the primary instance. To change the storage type of a read-only RDS instance, go to the instance details page to perform the required operations.
After changing ESSD to premium performance disk, you cannot change premium performance disk to other storage types. Please choose carefully.
Before changing ESSD to premium performance disk, make sure the instance has no unfinished backup jobs, otherwise it will affect the completion time of the disk configuration change task.
Procedure
New instances
When purchasing a new instance, you can select Premium Performance Disk as the storage type for the instance. For more information, see Create an ApsaraDB RDS for PostgreSQL instance.
Related API operations
API | Description |
When creating an instance, set the DBInstanceStorageType parameter to general_essd to use premium performance disk. |