What should a developer do to resolve the errors?
Initialize the database connection outside the handler function. Increase the max_user_connections value on the parameter group of the DB cluster. Restart the DB cluster.
Initialize the database connection outside the handler function. Use RDS Proxy instead of connecting directly to the DB cluster.
Use Amazon Simple Queue Service (Amazon SQS) FIFO queues to queue the orders. Ingest the orders into the database. Set the Lambda function’s concurrency to a value that equals the number of available database connections.
Use Amazon Simple Queue Service (Amazon SQS) FIFO queues to queue the orders. Ingest the orders into the database. Set the Lambda function’s concurrency to a value that is less than the number of available database connections.
Explanations:
While initializing the database connection outside the handler function can help reduce connection overhead, simply increasing the max_user_connections without managing connection usage can still lead to resource exhaustion during traffic spikes. Restarting the DB cluster is also not a suitable long-term solution.
Using RDS Proxy allows for connection pooling, which can help manage database connections efficiently, reducing the likelihood of hitting the “too many connections” error during high traffic. This approach also optimizes the number of active connections and can provide better performance for the Lambda function.
Although using SQS can help decouple the order processing from direct database writes, setting the Lambda function’s concurrency to match the number of available connections could still lead to issues if the traffic spikes. Without proper connection pooling, this solution does not effectively resolve the “too many connections” error.
Similar to option C, while using SQS is a good practice for handling spikes in load, simply setting the Lambda function’s concurrency to a value less than the number of connections does not inherently solve the issue. Without a connection management strategy like RDS Proxy, this could still result in connection issues during high traffic periods.
I plot that the answer is:
Initialize the database connection outside the handler function. Use RDS Proxy instead of connecting directly to the DB cluster.