Amazon DocumentDB Limits
This topic describes the resource 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.
Topics
Supported Instance Types
Amazon DocumentDB supports on-demand instances and the following instance types:
-
Memory Optimized:
-
Current Generation:
R5 instance types:
db.r5.large
,db.r5.2xlarge
,db.r5.4xlarge
,db.r5.12xlarge
,db.r5.24xlarge
.R4 instance types:
db.r4.large
,db.r4.2xlarge
,db.r4.4xlarge
,db.r4.8xlarge
,db.r4.16xlarge
.
-
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) |
|
3 |
US East (N. Virginia) |
|
6 |
US West (Oregon) |
|
4 |
Asia Pacific (Mumbai) |
|
2 |
Asia Pacific (Seoul) |
|
3 |
Asia Pacific (Sydney) |
|
2 |
Asia Pacific (Singapore) |
|
3 |
Asia Pacific (Tokyo) |
|
3 |
Canada (Central) |
|
3 |
Europe (Frankfurt) |
|
3 |
Europe (Ireland) |
|
3 |
Europe (London) |
|
3 |
Europe (Paris) |
|
3 |
Regional Limits
For certain management features, Amazon DocumentDB uses operational technology that is shared with Amazon Relational Database Service (Amazon RDS) and Amazon Neptune. The following table contains regional limits that are shared among Amazon DocumentDB, Amazon RDS, and Neptune.
The following limits are per AWS account per region.
Resource | Default Limit |
---|---|
Clusters | 40 |
Instances | 40 |
Event subscriptions | 20 |
Manual cluster snapshots | 100 |
Cluster parameter groups | 50 |
Read replicas per cluster | 15 |
VPC security groups per instance | 5 |
Subnet groups | 50 |
Subnets per subnet group | 20 |
Tags per resource | 50 |
You can take the following steps to request an increase for limits. These increases are not granted immediately, so it may take a couple of days for your increase to become effective.
To request a limit increase
-
Open the AWS Support Center page at https://console.aws.amazon.com/support/home, sign in if necessary, and choose Create case.
-
For Regarding, choose Service Limit Increase.
-
For Limit type, choose RDS from the list.
-
Complete the form. If this request is urgent, choose Phone as the method of contact instead of Web.
-
Choose Submit.
Aggregation Limits
The following table describes aggregation limits in Amazon DocumentDB.
Resource | Default Limit |
---|---|
Maximum number of supported stages | 500 |
Cluster Limits
The following table describes Amazon DocumentDB cluster limits.
Resource | Limit |
---|---|
Cluster size (sum of all collections and indexes) | 64 TB |
Database size (sum of all databases can't exceed cluster limit) | 64 TB |
Collection size (sum of all collections can't exceed cluster limit) – does not include the index size | 32 TB |
Collections per cluster | 100,000 |
Document size | 16 MB |
Document nesting depth | 100 levels |
Indexes per collection | 64 |
Index key size (for arrays, the entire array must be less than 2,048 bytes) | 2,048 bytes |
Keys in a compound index | 32 |
Number of users per cluster | 100 |
Maximum number of writes in a single batch command | 100,000 |
Instance Limits
The following table describes Amazon DocumentDB limits per instance.
Resource | Limit |
---|---|
Number of concurrent connections by instance type | db.r5.large – 1,100
db.r4.large – 1,100 |
db.r5.xlarge – 2,700
db.r4.xlarge – 2,700 |
|
db.r5.2xlarge – 4,500
db.r4.2xlarge – 4,500 |
|
db.r5.4xlarge – 4,500
db.r4.4xlarge – 4,500 |
|
db.r4.8xlarge – 4,500 |
|
db.r5.12xlarge – 4,500 |
|
db.r4.16xlarge – 4,500 |
|
db.r5.24xlarge – 4,500 |
|
Maximum number of open cursors per instance | 450 |
Naming Constraints
The following table describes naming constraints in Amazon DocumentDB.
Resource | Default Limit |
---|---|
Cluster identifier |
|
Instance identifier |
|
Master user name |
|
Master password |
|
Parameter group name |
|
Database name: <db> |
Length is [1–63] characters. |
Collection name: <col> |
Length is [1–57] characters. |
Fully qualified collection name: <db>.<col> |
Length is [3–120] characters. |
Index name: <col>$<index> |
Length is [3–63] characters. |
Fully qualified index name: <db>.<col>.$<index> |
Length is [6–127] characters. |
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.