This topic describes the concept, performance, performance limits, scenarios, billing, and related operations of premium performance disks to help you determine whether to use premium performance disks.
Overview
Premium performance disk is a new storage type supported by ApsaraDB RDS. It is compatible with all features of ESSD and supports I/O burst, Buffer Pool Extension (BPE), and data archiving to OSS.
Buffer Pool Extension (BPE)
After you enable Buffer Pool Extension (BPE), you can expand the cache pool size of your instance, implement cache acceleration, and improve the overall read and write performance of your RDS instance. It also significantly reduces the impact of I/O jitter on database operations and improves stability. This feature is suitable if you want to improve the I/O performance of the RDS instance without upgrading instance specifications or modifying business code. For more information, see Buffer Pool Extension (BPE) feature.
I/O burst
After you enable the I/O burst feature, the IOPS of the disk is not limited to the maximum IOPS, allowing you to obtain higher I/O capabilities during peak business periods to meet burst business requirements. This feature is suitable for handling high and fluctuating I/O loads. For more information, see I/O burst feature.
Data archiving
After you enable the data archiving feature for an RDS instance, you can migrate infrequently accessed data to an Object Storage Service (OSS) bucket. Compared with data storage in PL1 ESSDs, storing data in an OSS bucket helps you reduce costs by 80%. This feature is suitable if your RDS instance contains infrequently accessed or modified tables. For more information, see Data archiving feature.
Scope of application
RDS MySQL High-availability Edition and Cluster Edition.
Non-Serverless billing method: Premium performance disks are supported.
Serverless billing method: Not supported
Performance of premium performance disks
Baseline I/O performance
The baseline I/O performance of premium performance disks has been improved. The following table shows the differences in baseline performance improvement for premium performance disk instances with different storage capacities. For more information, see [Product/Feature Change] Baseline I/O performance improvement for RDS premium performance disks.
This performance improvement requires that the storage capacity of premium performance disk instances is not less than 100 GB.
After this performance improvement, when you use the I/O burst feature, it will be based on the improved baseline I/O performance.
Storage capacity of premium performance disk | Original baseline I/O performance (the same as that of PL1 ESSDs) | Improved baseline I/O performance | Increment |
100 GB ≤ Storage capacity < 1000 GB | I/O bandwidth: 125 MB/s to 350 MB/s IOPS: 6800 to 50000 | I/O bandwidth: 225 MB/s to 450 MB/s IOPS: 13200 to 56400 | I/O bandwidth: 100 MB/s IOPS: 6400 |
1000 GB ≤ Storage capacity < 2000 GB | I/O bandwidth: 350 MB/s IOPS: 50000 | I/O bandwidth: 500 MB/s IOPS: 59600 | I/O bandwidth: 150 MB/s IOPS: 9600 |
2000 GB ≤ Storage capacity < 4000 GB | I/O bandwidth: 350 MB/s IOPS: 50000 | I/O bandwidth: 550 MB/s IOPS: 62800 | I/O bandwidth: 200 MB/s IOPS: 12800 |
4000 GB ≤ Storage capacity < 16000 GB | I/O bandwidth: 350 MB/s IOPS: 50000 | I/O bandwidth: 600 MB/s IOPS: 66000 | I/O bandwidth: 250 MB/s IOPS: 16000 |
16000 GB ≤ Storage capacity < 64000 GB | I/O bandwidth: 350 MB/s IOPS: 50000 | I/O bandwidth: 700 MB/s IOPS: 72400 | I/O bandwidth: 350 MB/s IOPS: 22400 |
Performance of premium performance disk features
Buffer Pool Extension (BPE)
After you enable Buffer Pool Extension (BPE), you can effectively improve read and write performance, reduce SQL execution time, and reduce the impact of I/O jitter on database operations, improving stability. For more information, see Buffer Pool Extension (BPE) feature.
I/O burst
After you enable I/O burst for a premium performance disk, the maximum IOPS and throughput limits of the instance will increase. The differences between enabling and not enabling I/O burst are as follows:
After you enable the I/O burst feature for the primary node, the feature is also enabled for the secondary node. The feature is not enabled for read-only instances. You need to enable it on the details page of the read-only instance.
Scenario | Maximum IOPS | Maximum throughput |
I/O burst not enabled |
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I/O burst enabled |
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For information about
Increased IOPS valueandIncreased I/O bandwidth value, see Baseline I/O performance improvement for RDS premium performance disks.If the throughput of an RDS instance reaches the upper limit, the IOPS of the instance is affected. If the IOPS of an RDS instance reaches the upper limit, the throughput of the instance is affected.
The preceding formulas do not apply to disk instances with general-purpose instance types because general-purpose instance types share resources and cannot guarantee maximum IOPS and maximum I/O bandwidth.
For information about the maximum IOPS and maximum I/O bandwidth for instance types mentioned in the preceding formulas, see Primary ApsaraDB RDS for MySQL Standard Edition (formerly X86) instance types and Primary ApsaraDB RDS for MySQL Enterprise Edition (formerly ARM) instance types.
The following table describes how to calculate the IOPS that corresponds to the maximum I/O bandwidth mentioned in the preceding calculations.
RDS product
IOPS calculation method
Remarks
RDS MySQL
IOPS = Maximum I/O bandwidth for the instance type (Gbit/s) × 1024 × 1024/8/16
In this calculation, the value 8 indicates 8 bits, and 8 bits form a byte. The value 16 indicates that the amount of data involved in an I/O operation on an ApsaraDB RDS for MySQL instance is 16 KB.
Data archiving
After you enable the data archiving feature of premium performance disks and archive infrequently accessed data, you can reduce storage costs. The performance when accessing archived data is relatively low.
Scenarios
Buffer Pool Extension (BPE)
Buffer Pool Extension (BPE) is suitable for scenarios with high read I/O loads and extensive use of temporary tables.
I/O burst
Premium performance disks are suitable for handling high and fluctuating I/O loads.
Business peaks, large transactions, table scans, and queries that return large amounts of data can all cause I/O loads to increase. Sometimes CPU, memory, and storage space are relatively sufficient, but the I/O usage rate is close to or reaches 100%. In these scenarios, you must upgrade the instance specifications or storage type of your RDS instance. For example, you can upgrade the storage type from PL1 ESSD to PL2 ESSD.
If you do not upgrade the instance specifications or storage type, the I/O loads reach the upper limit. As a result, the instance performance decreases, queries time out, and connection errors occur.
If you upgrade instance specifications, the I/O performance can meet your business requirements, but the CPU, memory, and storage resources are idle and wasted.
If you upgrade the storage type, the I/O usage is increased within a short period of time, but storage resources are wasted and costs are increased when the I/O loads decrease.
The I/O burst feature of premium performance disks can solve these problems. After you enable the I/O burst feature, when I/O loads are high, I/O burst is automatically triggered to increase the I/O limit. When I/O loads decrease, the I/O limit is automatically restored, achieving serverless I/O performance and avoiding I/O performance and cost waste.
Data archiving
Data archiving is suitable if your RDS instance contains infrequently accessed or modified tables.
Limits
The storage capacity range supported by premium performance disks is 10 GB to 64,000 GB.
Premium performance disks cannot be changed to any other storage type, but ESSDs can be changed to premium performance disks. For more information, see Change ESSDs to premium performance disks.
Billing
Billable methods
Premium performance disk fee = RDS storage space fee + I/O burst fee + Buffer Pool Extension (BPE) fee + data archiving OSS fee.
For the billing details of each feature, see the following:
The Buffer Pool Extension (BPE) feature is free for RDS MySQL general-purpose instance types.
RDS storage space fee
There are differences in fees between ESSDs (PL2 and PL3) and premium performance disks. The difference is based on the order in the console at the time of the change.
Within a certain time period, the shorter the duration of high I/O, the more cost-effective premium performance disks are compared to PL2 and PL3 ESSDs.
Premium performance disk fee = Storage space fee + I/O burst fee + Buffer Pool Extension (BPE) fee + data archiving OSS fee.
You are charged for the storage capacity that you purchase for your RDS instance. The subscription and pay-as-you-go billing methods are supported. The billing method is the same as that for PL1 ESSDs. For more information, see Billable items.
In the following regions, premium performance disks offer more favorable pricing compared to PL1 ESSDs under different billing methods, and the unit price for storage space itself is lower than that of PL1 ESSDs.
China (Hong Kong), Singapore, Malaysia (Kuala Lumpur), Indonesia (Jakarta), Philippines (Manila), Thailand (Bangkok), Japan (Tokyo), South Korea (Seoul), US (Silicon Valley), US (Virginia), Germany (Frankfurt), UK (London), and UAE (Dubai).
In the following regions, the unit price for storage space of premium performance disks is the same as that of PL1 ESSDs.
China (Hangzhou), China (Shanghai), China (Beijing), China (Shenzhen), China (Nantong), China (Qingdao), China (Zhangjiakou), China (Hohhot), China (Ulanqab), China (Heyuan), China (Guangzhou), China (Chengdu)