Amazon DocumentDB Quotas and Limits - Amazon DocumentDB
Supported Instance TypesSupported RegionsRegional QuotasAggregation LimitsCluster LimitsInstance LimitsNaming ConstraintsTTL ConstraintsElastic cluster limitsElastic cluster shard limitsElastic cluster CPU, memory, connection, and cursor limits per shard

Amazon DocumentDB Quotas and Limits

This topic describes the resource quotas, limits, and naming constraints for Amazon DocumentDB (with MongoDB compatibility).

For certain management features, Amazon DocumentDB uses operational technology that is shared with Amazon Relational Database Service (Amazon RDS) and Amazon Neptune.

Supported Instance Types

Amazon DocumentDB supports on-demand instances and the following instance types:

  • Memory Optimized:

    • R6G instance types: db.r6g.large, db.r6g.2xlarge, db.r6g.4xlarge, db.r6g.8xlarge, db.r6g.12xlarge, db.r6g.16xlarge.

    • R5 instance types: db.r5.large, db.r5.2xlarge, db.r5.4xlarge, db.r5.8xlarge, db.r5.12xlarge, db.r5.16xlarge db.r5.24xlarge.

    • R4 instance types: db.r4.large, db.r4.2xlarge, db.r4.4xlarge, db.r4.8xlarge, db.r4.16xlarge.

  • Burstable Performance:

    • T4G instance types: db.t4g.medium.

    • T3 instance types: db.t3.medium.

For more information on the supported instance types and their specifications, see Instance Class Specifications.

Supported Regions

Amazon DocumentDB is available in the following AWS regions:

Region Name Region Availability Zones (compute)

US East (Ohio)

us-east-2

3

US East (N. Virginia)

us-east-1

6

US West (Oregon)

us-west-2

4

South America (São Paulo)

sa-east-1

3

Asia Pacific (Hong Kong)

ap-east-1

3

Asia Pacific (Hyderabad)

ap-south-2

3

Asia Pacific (Mumbai)

ap-south-1

3

Asia Pacific (Seoul)

ap-northeast-2

4

Asia Pacific (Singapore)

ap-southeast-1

3

Asia Pacific (Sydney)

ap-southeast-2

3

Asia Pacific (Tokyo)

ap-northeast-1

3

Canada (Central)

ca-central-1

3

China (Beijing) Region

cn-north-1

3

China (Ningxia)

cn-northwest-1

3

Europe (Frankfurt)

eu-central-1

3

Europe (Ireland)

eu-west-1

3

Europe (London)

eu-west-2

3

Europe (Milan)

eu-south-1

3

Europe (Paris)

eu-west-3

3

Middle East (UAE)

me-central-1

3
AWS GovCloud (US-West)

us-gov-west-1

3
AWS GovCloud (US-East)

us-gov-east-1

3

Regional Quotas

For certain management features, Amazon DocumentDB uses operational technology that is shared with Amazon Relational Database Service (Amazon RDS). The following table contains regional limits that are shared among Amazon DocumentDB and Amazon RDS.

Note

The Amazon RDS shared technology described above only applies to Amazon DocumentDB instance-based clusters. Amazon DocumentDB elastic clusters do not share technology with Amazon RDS.

The following limits apply to Amazon DocumentDB instance-based clusters and are per AWS account per region.

Resource AWS default limit
Clusters 40
Cluster parameter groups 50
Event subscriptions 20
Instances 40
Manual cluster snapshots 100
Read replicas per cluster 15
Subnet groups 50
Subnets per subnet group 20
Tags per resource 50
VPC security groups per instance 5

The following limits apply to Amazon DocumentDB elastic clusters and are per AWS account per region.

Resource AWS default limit
Elastic clusters 20
Elastic clusters vCPU 1024
Manual elastic cluster snapshot 20

You can use Service Quotas to request an increase for a quota, if the quota is adjustable. Some requests are automatically resolved, while others are submitted to AWS Support. You can track the status of a quota increase request that is submitted to AWS Support. Requests to increase service quotas do not receive priority support. If you have an urgent request, please contact AWS Support. For more information on Service Quotas, see What Is Service Quotas?

To request a quota increase for Amazon DocumentDB:

  1. Open the Service Quotas console at https://console.aws.amazon.com/servicequotas and, if necessary, sign in.

  2. In the navigation pane, choose AWS services.

  3. Select Amazon DocumentDB (with MongoDB compatibility) or Amazon DocumentDB Elastic Cluster from the list, or type either in the search field.

  4. If the quota is adjustable, you can select its radio button or its name, and then choose Request quota increase from the top right of the page.

  5. For Change quota value, enter the new value. The new value must be greater than the current value.

  6. Choose Request. After the request is resolved, the Applied quota value for the quota is set to the new value.

  7. To view any pending or recently resolved requests, choose Dashboard from the navigation pane. For pending requests, choose the status of the request to open the request receipt. The initial status of a request is Pending. After the status changes to Quota requested, you'll see the case number with AWS Support. Choose the case number to open the ticket for your request.

Aggregation Limits

The following table describes aggregation limits in Amazon DocumentDB.

Resource Limit
Maximum number of supported stages 500

Cluster Limits

The following table describes Amazon DocumentDB instance-based cluster limits.

Resource Limit
Cluster size (sum of all collections and indexes) 128 TiB
Collection size
 (sum of all collections can't exceed cluster limit) – does not include the index size 32 TB
Collections per cluster 100,000
Databases per cluster 100,000
Database size (sum of all databases can't exceed cluster limit) 128 TiB
Document nesting depth 200 levels
Document size 16 MB
Index key size 2,048 bytes
Indexes per collection 64
Keys in a compound index 32
Maximum number of writes in a single batch command 100,000
Number of users per cluster 1000

Instance Limits

The following table describes Amazon DocumentDB limits per instance.

Instance Type Instance Memory (GiB) Connections (all) Cursor Limit Open Transactions Connections (active)
T3.medium 4 500 30 50 102
T4G.medium 4 500 30 50 102
R4.large 15.25 1700 450 N/A 1100
R4.xlarge 30.5 3400 450 N/A 2700
R4.2xlarge 61 6800 450 N/A 4500
R4.4xlarge 122 13600 725 N/A 4500
R4.8xlarge 288 27200 1450 N/A 4500
R4.16xlarge 488 30000 2900 N/A 4500
R5.large 16 1700 450 200 1100
R5.xlarge 32 3500 450 400 2700
R5.2xlarge 64 7100 450 800 4500
R5.4xlarge 128 14200 760 1600 4500
R5.8xlarge 256 28400 1520 3200 4500
R5.12xlarge 383 30000 2280 4800 4500
R5.16xlarge 512 30000 3040 6400 4500
R5.24xlarge 768 30000 4560 9600 4500
R6G.large 16 1700 450 200 1100
R6G.xlarge 32 3500 450 400 2700
R6G.2xlarge 64 7100 450 800 4500
R6G.4xlarge 128 14200 760 1600 4500
R6G.8xlarge 256 28400 1520 3200 4500
R6G.12xlarge 383 30000 2280 4800 4500
R6G.16xlarge 512 30000 3040 6400 4500

You can monitor and alarm on the per instance limits using the following CloudWatch metrics. For more on Amazon DocumentDB CloudWatch metrics, see Monitoring Amazon DocumentDB with CloudWatch.

Limit CloudWatch Metrics
Instance Memory FreeableMemory
Connections DatabaseConnectionsMax
Cursors DatabaseCursorsMax
Transactions TransactionsOpenMax

Naming Constraints

The following table describes naming constraints in Amazon DocumentDB.

Resource Default Limit
Cluster identifier

  • Length is [1–63] letters, numbers, or hyphens.

  • First character must be a letter.

  • Cannot end with a hyphen or contain two consecutive hyphens.

  • Must be unique for all clusters (across Amazon RDS, Amazon Neptune, and Amazon DocumentDB) per AWS account, per Region.
Collection name: <col>

Length is [1–57] characters.
Database name: <db>

Length is [1–63] characters.
Fully qualified collection name: <db>.<col> Length is [3–120] characters.
Fully qualified index name: <db>.<col>.$<index> Length is [6–127] characters.
Index name: <col>$<index>

Length is [3–63] characters.
Instance identifier

  • Length is [1–63] letters, numbers, or hyphens

  • First character must be a letter

  • Cannot end with a hyphen or contain two consecutive hyphens

  • Must be unique for all instances (across Amazon RDS, Amazon Neptune, and Amazon DocumentDB) per AWS account, per Region.
Master password

  • Length is [8-100] printable ASCII characters.

  • Can use any printable ASCII characters except for the following:

    • / (forward slash)

    • " (double quotation mark)

    • @ (at symbol)
Master user name

  • Length is [1-63] alphanumeric characters.

  • First character must be a letter.

  • Cannot be a word reserved by the database engine.
Parameter group name

  • Length is [1–255] alphanumeric characters.

  • First character must be a letter.

  • Cannot end with a hyphen or contain two consecutive hyphens.

TTL Constraints

Deletes from a TTL index are not guaranteed within a specific timeframe and are best effort. Factors like instance resource utilization, document size, and overall throughput can affect the timing of a TTL delete.

Elastic cluster limits

The following table describes maximum limits in Amazon DocumentDB elastic clusters.

Resource Limit
Elastic clusters per region 20
vCPU summed across all elastic clusters per region 1024
Manual cluster snapshots per region 20
Shards per cluster 32
Storage per cluster (when data is evenly distributed by shard-key) 4 PiB
Connections to cluster The lower value of either 300,000 or the number of shards x the connection limit associated with vCPU per shard
UnSharded collection size 32TB
Sharded collection size (when data is evenly distributed by shard-key) 1PB
Databases per cluster 10,000
UnSharded collections per cluster 100,000
Sharded collections per cluster 1000
Users per cluster 100
Writes in a single batch command 100,000
Indexes per collection 64
Document nesting depth 100 levels
Document size 16MB
Index key size 2048 bytes
Keys in a compound index 32

Elastic cluster shard limits

The following table describes maximum shard limits in Amazon DocumentDB elastic clusters.

Resource Limit
vCPU per shard instance 64
Instances per shard 16
Strorage per shard 128 TiB
Storage per collection per shard 32TB

Elastic cluster CPU, memory, connection, and cursor limits per shard

The following table describes maximum CPU, memory, connection, and cursor limits in Amazon DocumentDB elastic cluster shards.

vCPUs per shard Instance memory (GiB) Connection limit Cursor limit
2 16 1700 450
4 32 3500 450
8 64 7100 450
16 128 14200 760
32 256 28400 1520
48 383 30000 2280
64 512 30000 3040