Community Edition instances that use cloud disks - ApsaraDB for Redis

This topic describes the specifications of Community Edition instances that use cloud disks. The specifications include the memory capacity, maximum number of connections, maximum bandwidth, and queries per second (QPS) reference value.

Instance types

The following tables list the specifications of a single shard. The overall performance of a cluster or read/write splitting instance can be calculated by using the following formula: Overall performance = Performance of a single shard × Number of shards.

Note

The ESSDs listed in these tables are used only to support the operating of the system, such as storing logs, supporting temporary file backup, and storing Append Only Files (AOFs). They are not intended for data storage.
For more information about the differences between the direct connection mode and the proxy mode that are supported by cluster instances, see Cluster master-replica instances.
You can change the number of shards in cluster instances that use cloud disks. For more information, see Adjust the number of shards for an ApsaraDB for Redis cloud-native instance.

Shard specifications of standard and cluster instances in direct connection mode

The specifications listed in the following table are applicable to cloud disk-based standard and cluster instances in direct connection mode.

Table 1. Shard specifications of standard and cluster instances in direct connection mode
Instance type	InstanceClass value (used in API operations)	CPU cores	Memory (GB)	ESSD capacity (GB)	Maximum bandwidth (MB/s)	Maximum connections	QPS reference value
256 MB Community Edition	redis.shard.micro.ce	2	0.25	1.25	24	10,000	100,000
1 GB Community Edition	redis.shard.small.ce	2	1	5	48	10,000	100,000
2 GB Community Edition	redis.shard.mid.ce	2	2	10	96	10,000	100,000
4 GB Community Edition	redis.shard.large.ce	2	4	20	96	10,000	100,000
8 GB Community Edition	redis.shard.xlarge.ce	2	8	40	96	10,000	100,000
16 GB Community Edition	redis.shard.2xlarge.ce	2	16	80	96	10,000	100,000
24 GB Community Edition	redis.shard.3xlarge.ce	2	24	120	96	10,000	100,000
32 GB Community Edition	redis.shard.4xlarge.ce	2	32	160	96	10,000	100,000
64 GB Community Edition	redis.shard.8xlarge.ce	2	64	320	96	10,000	100,000

Note

Cluster instances do not support the 256 MB Community Edition instance type.

Shard specifications of cluster instances in proxy mode and read/write splitting instances

The specifications listed in the following table are applicable to cloud disk-based cluster instances in proxy mode and cloud disk-based read/write splitting instances.

Table 2. Shard specifications of cluster instances in proxy mode and read/write splitting instances
Instance type	InstanceClass value (used in API operations)	CPU cores	Memory (GB)	ESSD capacity (GB)	Maximum bandwidth (MB/s)	Maximum connections	QPS reference value
1 GB Community Edition	redis.shard.with.proxy.small.ce	2	1	5	48	10,000	100,000
2 GB Community Edition	redis.shard.with.proxy.mid.ce	2	2	10	96	10,000	100,000
4 GB Community Edition	redis.shard.with.proxy.large.ce	2	4	20	96	10,000	100,000
8 GB Community Edition	redis.shard.with.proxy.xlarge.ce	2	8	40	96	10,000	100,000
16 GB Community Edition	redis.shard.with.proxy.2xlarge.ce	2	16	80	96	10,000	100,000
24 GB Community Edition	redis.shard.with.proxy.3xlarge.ce	2	24	120	96	10,000	100,000
32 GB Community Edition	redis.shard.with.proxy.4xlarge.ce	2	32	160	96	10,000	100,000
64 GB Community Edition	redis.shard.with.proxy.8xlarge.ce	2	64	320	96	10,000	100,000

Performance description

Architecture

Performance description

Standard instance

The overall performance of standard instances is as described in the preceding table.

Cluster instance in direct connection mode

Cluster instance in proxy mode

Read/write splitting instances

Overall performance of an instance = Performance of a single shard × Number of shards.

If an instance has four shards of the redis.shard.with.proxy.small.ce type, the following items show the performance of a single shard:

Number of CPU cores: 2
Bandwidth: 24 MB/s
Maximum number of connections: 10,000
QPS reference value: 100,000

The following items show the performance of the instance:

Number of CPU cores: 8
Bandwidth: 96 MB/s
Maximum number of connections: 40,000
QPS reference value: 400,000

Notes about CPU cores

To ensure service stability, the system reserves a CPU core to process background tasks. In a cluster instance or a read/write splitting instance, the system reserves a CPU core for each data shard or each read replica to process background tasks.

Calculation rules for bandwidth

The bandwidths in the preceding tables are the bandwidth of a single shard. The total bandwidth of a cluster instance or read/write splitting instance is the total bandwidth of all shard nodes in the instance.
The maximum bandwidth of cluster instances in proxy mode is 2,048 MB/s. After this upper limit is reached, the bandwidth does not increase even if the number of shards increases. Cluster instances in direct connection mode have no bandwidth limit.
The bandwidths apply to the upstream and downstream bandwidths. For example, if the bandwidth of an instance is 24 MB/s, the upstream and downstream bandwidths of the instance are both 24 MB/s.
The bandwidths in the preceding tables are the internal bandwidth of instances. The public bandwidth is determined by the internal bandwidth and is limited by the bandwidth of the connection between an instance and the client. We recommend that you connect to the instance over an internal network to maximize performance.

Calculation rules for connections

Parameter	Description
Maximum number of connections	Proxy mode:the maximum number of connections to an instance is 500,000. If the upper limit of 500,000 connections is reached, subsequent connections cannot be established even if you add more shards or nodes. Direct connection mode:the maximum number of connections for a single shard is 10,000. The maximum number of connections for an instance can be calculated by using the following formula: Number of shards × 10,000.
Number of new connections per second	The maximum number of new connections per second refers to the number of connections that are allowed to be established per second. The following example shows how the maximum number of new connections per second affects the maximum number of connections at a specific second: For example, assume that the maximum number of new connections to an instance per second is 10,000, the maximum number of connections to the instance is 50,000, and the actual number of connections at the Nth second after the instance starts to run is 12,000. In this case, at the (N+1)th second, the maximum number of connections is 22,000. This value is calculated by using the following formula: 12,000 + 10,000. Note If the instance is connected in direct connection mode, connection performance degrades because proxy nodes are bypassed. For more information about the direct connection mode, see Enable the direct connection mode. The maximum number of new connections per second for a single data shard is 2,000. For example, if an instance has four data shards, the maximum number of new connections per second for the instance is 8,000.

FAQ

Q: Why is the actual bandwidth of my instance different from that described in this topic?

A: The bandwidths of specific instance types may be adjusted after the service is upgraded. If the bandwidth of your instance is different from that described in this topic, change your instance specifications to update the bandwidth. Make sure that you select the same instance type when you change the specifications. For more information, see Change the configurations of an instance.