Billing Method |
- Subscription: A subscription-billed instance is an instance that you can subscribe to for a specified
period of time and pay for up front. Subscription billing is more cost-effective than
pay-as-you-go billing. Therefore, we recommend that you select subscription billing
with a longer commitment. You can receive larger discounts for longer subscription
periods.
- Pay-As-You-Go: A pay-as-you-go-billed instance is charged per hour based on your actual resource
usage. We recommend that you select pay-as-you-go billing for short-term use. If you
no longer need your pay-as-you-go-billed instance, you can release it to reduce costs.
Note A maximum of 30 pay-as-you-go-billed instances are allowed per Alibaba Cloud account.
If you want to increase this quota, submit a ticket.
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Region |
The region to which the RDS instance belongs.
- After you confirm your purchase order, you cannot change the selected region.
- We recommend that you select a region that is in close proximity to the geographic
location where your users reside. This increases the access speeds of your users.
- The RDS instance must reside in the same region as the ECS instance that you want
to connect. If the RDS and ECS instances reside in different regions, they cannot
communicate over an internal network and therefore cannot deliver optimal performance.
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Database Engine |
The database engine and engine version that the RDS instance is running. Select PostgreSQL. Supported PostgreSQL versions are 9.4, 10, 11, 12, and 13.
Note The available database engines and versions vary based on the selected region.
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Edition |
- Basic: The database system consists of only one RDS instance. Computing is separated from
storage to increase cost-effectiveness.
- High-availability: The database system adopts the classic high-availability architecture that consists
of one primary instance and one secondary instance.
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Storage Type |
- Local SSD: A local SSD resides on the same server as the database engine. You can store data
on local SSDs to reduce I/O latency.
- Enhanced SSD: An enhanced SSD is an ultra-high performance disk that is developed by Alibaba Cloud
based on the next-generation distributed block storage architecture. It integrates
25 Gigabit Ethernet and remote direct memory access (RDMA) technologies. This reduces
one-way latency and delivers up to 1 million random input/output operations per second
(IOPS). Supported enhanced SSDs are available in the following three performance levels
(PLs):
- PL1 (Enhanced SSD): An enhanced SSD of PL1 is a regular enhanced SSD.
- PL2 (ESSD PL2): An enhanced SSD of PL2 delivers IOPS and throughput that are twice
as high as those delivered by an enhanced SSD of PL1.
- PL3 (ESSD PL3): An enhanced SSD of PL3 delivers IOPS that is 20 times as high as the
IOPS delivered by an enhanced SSD of PL1. It also delivers throughput that is 11 times
as high as the throughput delivered by an enhanced SSD of PL1. Enhanced SSDs of PL3
are suitable for workloads that require high I/O performance in processing concurrent
requests and stable read/write latency.
- Standard SSD: A standard SSD is an elastic block storage device that is designed based on the
distributed storage architecture. You can store data on standard SSDs to separate
computing from storage.
For more information, see Storage types.
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Zone |
The zone to which the RDS instance belongs. A zone is an independent physical location
within a region. The Zone of Primary Node parameter specifies the zone to which the primary RDS instance belongs. The Zone of Secondary Node parameter specifies the zone to which the secondary RDS instance belongs.
You can select the Single-zone Deployment or Multi-zone Development method.
- Single-zone Deployment: The Zone of Primary Node and the Zone of Secondary Node are the same.
- Multi-zone Deployment: The Zone of Primary Node and the Zone of Secondary Node are different. After you specify the Zone of Primary Node, the system automatically allocates the Zone of Secondary Node.
The multi-zone deployment method provides zone-level disaster recovery. We recommend
that you select the multi-zone deployment method.
Note
- After the RDS instance is created, you can view information about the RDS instance
and its secondary RDS instance on the Service Availability page.
- If you select the RDS Basic Edition, the database system consists of only one RDS
instance and supports only the single-zone deployment method.
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Instance Type |
- Entry-level: belongs to the general-purpose instance family. A general-purpose instance exclusively
occupies the allocated memory and I/O resources. However, it shares CPU and storage
resources with the other general-purpose instances that are deployed on the same server.
- Dedicated Instance (Enterprise-level): belongs to the dedicated instance family or the dedicated host instance family.
A dedicated instance exclusively occupies the allocated CPU, memory, storage, and
I/O resources. The top configuration of the dedicated instance family is the dedicated
host instance family. A dedicated host instance exclusively occupies all of the CPU,
memory, storage, and I/O resources on the server where it is deployed.
Note Each instance type supports a specific number of CPU cores, memory capacity, maximum
number of connections, and maximum IOPS. For more information, see Primary instance types.
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Capacity |
The storage capacity that the read-only RDS instance has available to store data files,
system files, binary log files, and transaction files. The storage capacity increases
in increments of 5 GB.
Note The dedicated instance family supports exclusive allocations of resources. Therefore,
the storage capacity of each instance type with local SSDs in this family is fixed.
For more information, see Primary instance types.
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