DynamoDB online store

Description

The DynamoDB online store provides support for materializing feature values into AWS DynamoDB.

Getting started

In order to use this online store, you'll need to run pip install 'feast[aws]'. You can then get started with the command feast init REPO_NAME -t aws.

Example

{% code title="feature_store.yaml" %}

yaml

project: my_feature_repo
registry: data/registry.db
provider: aws
online_store:
  type: dynamodb
  region: us-west-2

{% endcode %}

The full set of configuration options is available in DynamoDBOnlineStoreConfig.

Configuration

Below is a example with performance tuning options:

{% code title="feature_store.yaml" %}

yaml

project: my_feature_repo
registry: data/registry.db
provider: aws
online_store:
  type: dynamodb
  region: us-west-2
  batch_size: 100
  max_read_workers: 10
  consistent_reads: false

{% endcode %}

Configuration Options

Option	Type	Default	Description
`region`	string		AWS region for DynamoDB
`table_name_template`	string	`{project}.{table_name}`	Template for table names
`batch_size`	int	`100`	Number of items per BatchGetItem/BatchWriteItem request (max 100)
`max_read_workers`	int	`10`	Maximum parallel threads for batch read operations. Higher values improve throughput for large batch reads but increase resource usage
`consistent_reads`	bool	`false`	Whether to use strongly consistent reads (higher latency, guaranteed latest data)
`tags`	dict	`null`	AWS resource tags added to each table
`session_based_auth`	bool	`false`	Use AWS session-based client authentication

Performance Tuning

Parallel Batch Reads: When reading features for many entities, DynamoDB's BatchGetItem is limited to 100 items per request. For 500 entities, this requires 5 batch requests. The max_read_workers option controls how many of these batches execute in parallel:

Sequential (old behavior): 5 batches × 10ms = 50ms total
Parallel (with max_read_workers: 10): 5 batches in parallel ≈ 10ms total

For high-throughput workloads with large entity counts, increase max_read_workers (up to 20-30) based on your DynamoDB capacity and network conditions.

Batch Size: Increase batch_size up to 100 to reduce the number of API calls. However, larger batches may hit DynamoDB's 16MB response limit for tables with large feature values.

Permissions

Feast requires the following permissions in order to execute commands for DynamoDB online store:

Command	Permissions	Resources
Apply	<p>dynamodb:CreateTable</p><p>dynamodb:DescribeTable</p><p>dynamodb:DeleteTable</p><p>dynamodb:TagResource</p>	arn:aws:dynamodb:<region>:<account_id>:table/*
Materialize	dynamodb.BatchWriteItem	arn:aws:dynamodb:<region>:<account_id>:table/*
Get Online Features	dynamodb.BatchGetItem	arn:aws:dynamodb:<region>:<account_id>:table/*

The following inline policy can be used to grant Feast the necessary permissions:

javascript

{
    "Statement": [
        {
            "Action": [
                "dynamodb:CreateTable",
                "dynamodb:DescribeTable",
                "dynamodb:DeleteTable",
                "dynamodb:TagResource",
                "dynamodb:BatchWriteItem",
                "dynamodb:BatchGetItem"
            ],
            "Effect": "Allow",
            "Resource": [
                "arn:aws:dynamodb:<region>:<account_id>:table/*"
            ]
        }
    ],
    "Version": "2012-10-17"
}

Lastly, this IAM role needs to be associated with the desired Redshift cluster. Please follow the official AWS guide for the necessary steps here.

Functionality Matrix

The set of functionality supported by online stores is described in detail here. Below is a matrix indicating which functionality is supported by the DynamoDB online store.

	DynamoDB
write feature values to the online store	yes
read feature values from the online store	yes
update infrastructure (e.g. tables) in the online store	yes
teardown infrastructure (e.g. tables) in the online store	yes
generate a plan of infrastructure changes	no
support for on-demand transforms	yes
readable by Python SDK	yes
readable by Java	no
readable by Go	no
support for entityless feature views	yes
support for concurrent writing to the same key	no
support for ttl (time to live) at retrieval	no
support for deleting expired data	no
collocated by feature view	yes
collocated by feature service	no
collocated by entity key	no

To compare this set of functionality against other online stores, please see the full functionality matrix.