dynamoDB DAX Flashcards
What is DynamoDB Accelerator (DAX)?
DynamoDB Accelerator (DAX) is a highly available in-memory cache for DynamoDB, capable of delivering response times in microseconds for millions of requests per second.
How many nodes are recommended for a highly available DAX cluster spread across AZs?
Three nodes are recommended for a highly available DAX cluster spread across Availability Zones (AZs).
What is a node in a DAX cluster?
A node is an EC2 instance with an instance of the DAX software and a single replica of the cached data.
How does DAX handle primary and replica nodes?
Nodes in a DAX cluster can be either primary or replica, but there is only one primary node decided by DAX.
What determines the read throughput of a DAX cluster?
The read throughput of a DAX cluster depends on its cluster size.
How can you scale a DAX cluster?
You can scale a DAX cluster horizontally or vertically.
Where does DAX run?
DAX runs in a Virtual Private Cloud (VPC) and is not accessible over the public internet.
What use cases is DAX ideal for?
DAX is ideal for read-intensive applications that require response times in microseconds, to mitigate the effects of hot partitions, and to cache large data sets that are repeatedly read to save Read Capacity Units (RCU).
What are the scenarios where DAX is not ideal?
DAX is not ideal for apps that require strongly consistent reads, write-heavy applications, or when an existing caching layer like Elasticache or Redis is already in use and custom caching logic is desired.