This topic describes the concept, performance, maximum performance, scenarios, billing rules, and related operations of general Enterprise SSDs (ESSDs).
Introduction
The general ESSD is a new storage type supported by ApsaraDB RDS. General ESSDs are compatible with all features of ESSDs and support the I/O burst, I/O acceleration, and data archiving features. General ESSDs provide better baseline I/O performance than performance level 1 (PL1) ESSDs.
I/O acceleration
If you enable the I/O acceleration feature of general ESSDs for an RDS instance, the system expands the size of the buffer pool of your RDS instance. This accelerates caching and improves the read/write performance of the RDS instance. The feature also significantly reduces the impact of the I/O jitter of general ESSDs on the RDS instance and improves the stability of the RDS instance. The feature is suitable if you want to improve the I/O performance of the RDS instance without the need to upgrade instance specifications or modify business code. For more information, see Use the I/O acceleration feature of general ESSDs.
I/O burst
If you enable the I/O burst feature of general ESSDs for an RDS instance, the IOPS of general ESSDs is no longer limited by the maximum IOPS. This improves the I/O performance of the RDS instance to handle workload bursts during peak hours. The feature is suitable for scenarios in which I/O loads are heavy and fluctuate. For more information, see Use the I/O burst feature of general ESSDs.
Data archiving
If you enable the data archiving feature of general ESSDs for an RDS instance, you can store data that is infrequently accessed to an OSS bucket and the storage costs are reduced by 80% compared to PL1 ESSDs. The feature is suitable if your RDS instance contains infrequently accessed or modified tables. For more information, see Use the data archiving feature of general ESSDs.
Applicable services
General ESSDs are supported for all RDS instances that use cloud disks.
Serverless RDS instances that run MySQL support only the I/O burst feature of general ESSDs.
Performance of general ESSDs
Baseline I/O performance
The increase in baseline I/O performance of general ESSDs may vary based on the storage capacity of the general ESSDs. The following table describes the details. For more information, see [Product changes/Feature changes] The baseline I/O performance of the general ESSDs of ApsaraDB RDS instances is increased.
In this example, the storage capacity of the RDS instance that uses general ESSDs is greater than or equal to 100 GB.
After the baseline I/O performance is increased for an RDS instance with the I/O burst feature enabled, the I/O burst feature is provided based on the increased baseline I/O performance.
Storage capacity of the general ESSD | Baseline before the increase (the same as that of PL1 ESSDs) | Baseline after the increase | Increment |
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 |
Performance of general ESSDs
I/O acceleration
If you enable the I/O acceleration feature of general ESSDs for an RDS instance, the read/write performance of the RDS instance is improved, the SQL execution time is shortened, the impact of the I/O jitter on database operations is reduced, and instance stability is enhanced. For more information, see Use the I/O acceleration feature of general ESSDs.
I/O burst
If you enable the I/O burst feature of general ESSDs for an RDS instance, the maximum IOPS and maximum throughput of the RDS instance are increased. The following table compares the maximum IOPS and maximum throughput of an RDS instance before and after the I/O burst feature is enabled for the RDS instance.
If you enable the I/O burst feature for the primary RDS instance, the I/O burst feature is automatically enabled for the secondary RDS instance. If you want to enable the I/O burst feature for the read-only RDS instances of the primary RDS instance, you must go to the instance details page.
Scenario | Maximum IOPS | Maximum throughput |
I/O burst disabled |
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I/O burst enabled |
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For more information about
IOPS incrementandI/O bandwidth increment, see [Product changes/Feature changes] Baseline I/O improvement of general ESSDs.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 calculations do not apply to RDS instances that use cloud disks and general-purpose instance types because these types of RDS instances share resources. As a result, the maximum IOPS and maximum I/O bandwidth cannot be guaranteed. For more information, see Instance types for primary ApsaraDB RDS for PostgreSQL instances.
For more information about the maximum IOPS and maximum I/O bandwidth of specific instance types, see Instance types for standard primary ApsaraDB RDS for MySQL instances (original x86 architecture) and Instance types for YiTian primary ApsaraDB RDS for MySQL instances (original ARM architecture).
The following table describes how to calculate the IOPS that corresponds to the maximum I/O bandwidth mentioned in the preceding calculations.
Service
IOPS calculation
Remarks
ApsaraDB RDS for 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
The data archiving feature of general ESSDs allows you to store data that is infrequently accessed to OSS buckets. This reduces storage costs but degrades the performance when you access the archived data.
Scenarios
I/O acceleration
I/O acceleration is suitable for scenarios in which read I/O loads are heavy and temporary tables are frequently used.
I/O burst
I/O burst is suitable for scenarios in which I/O loads are heavy and fluctuate.
I/O loads increase due to heavy workloads, large transactions, full table scans, and queries that return a large amount of data. In some cases, the I/O usage may approach or reach 100% even if the CPU, memory, and storage resources are sufficient. 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 ESSD performance level 1 (PL1) to ESSD PL2.
If you do not upgrade the instance specifications or storage type, the I/O loads can exceed 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 is sufficient, but CPU, memory, and storage resources may be 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.
You can use the I/O burst feature to resolve the preceding issues. If I/O loads increase after the I/O burst feature is enabled, an I/O burst is automatically triggered to increase the maximum I/O throughput. When I/O loads decrease, the maximum I/O throughput is automatically restored. This feature helps deliver serverless I/O performance, ensures optimal I/O performance, and reduces costs.
Data archiving
Data archiving is suitable if your RDS instance contains infrequently accessed or modified tables.
Limits
The storage capacity of a general ESSD ranges from 10 GB to 64,000 GB.
You cannot change the storage type of your RDS instance from general ESSD to a different storage type. However, you can change the storage type from ESSD to general ESSD. For more information, see Change the storage type from ESSD to general ESSD.
Billing rules
Billing
General ESSD fee = Fee for the storage capacity that your purchase for your RDS instance + I/O burst fee + I/O acceleration fee + Data archiving fee
For more information about the billing details of each feature, see the following topics:
If your RDS instance uses a general-purpose instance type, you can use the I/O acceleration feature free of charge.
Fee for the storage capacity that you purchase for your RDS instance
A PL2 ESSD, a PL3 ESSD, and a general ESSD have different unit prices. You can view the price difference for the storage type change in the ApsaraDB RDS console.
Within a specific time period, if an RDS instance handles a large number of I/O operations for a shorter period of time, general ESSDs are more cost-effective than PL2 ESSDs and PL3 ESSDs.
General ESSD fee = Fee for the storage capacity that you purchase for your RDS instance + I/O burst fee + I/O acceleration fee + Data archiving 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 rules are the same as those of a PL1 ESSD. For more information, see Billable items.
In the following regions, general ESSDs are more cost-effective than PL1 ESSDs regardless of the billing method, and the unit price of a general ESSD is lower than the unit price of a PL1 ESSD:
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)
NoteThe price difference between a general ESSD and a PL1 ESSD varies based on the billing method.
If you use the pay-as-you-go billing method, general ESSDs can be up to 60% more cost-effective than PL1 ESSDs.
If you use the subscription billing method, general ESSDs can be up to 43% more cost-effective than PL1 ESSDs.
In the following regions, the unit price of a general ESSD is the same as the unit price of a PL1 ESSD:
China (Hangzhou), China (Shanghai), China (Beijing), China (Shenzhen), China (Nantong), China (Qingdao), China (Zhangjiakou), China (Hohhot), China (Ulanqab), China (Heyuan), China (Guangzhou), and China (Chengdu)