AWS Lambda Cold Start Performance implementing Node.js 14.x and Amazon RDS
I keep running into I've been struggling with this for a few days now and could really use some help. I'm integrating two systems and I'm experiencing important cold start times with my AWS Lambda function that uses Node.js 14.x to connect to an Amazon RDS instance... The Lambda function is supposed to handle image uploads and store metadata in the RDS database, but during peak hours, I'm seeing cold starts exceeding 3 seconds, which is affecting user experience. I have already implemented the following optimizations: I switched to the Node.js 14.x runtime from Node.js 12.x, ensured my RDS instance is in the same region as my Lambda, and increased the Lambda's memory allocation to 1024 MB. However, these changes have not significantly improved the cold start times. Here’s a simplified version of my Lambda function: ```javascript const AWS = require('aws-sdk'); const mysql = require('mysql2/promise'); // Creating the RDS client outside of the handler for warm starts const pool = mysql.createPool({ host: 'your-rds-endpoint', user: 'your-username', password: 'your-password', database: 'your-database' }); exports.handler = async (event) => { try { const connection = await pool.getConnection(); const [rows] = await connection.query('SELECT * FROM Metadata'); connection.release(); return rows; } catch (behavior) { console.behavior('behavior connecting to the database:', behavior); throw new behavior('Database connection failed'); } }; ``` Additionally, I have configured the Lambda to use provisioned concurrency, but I’m still seeing cold starts during bursts of traffic. I’ve tried enabling VPC endpoints to connect to RDS, but that didn’t yield any performance benefits either. Are there any other strategies or best practices I can implement to reduce cold start times for this setup? Any insights into optimizing the Lambda function further would be greatly appreciated! My development environment is macOS. What am I doing wrong? For reference, this is a production desktop app. Thanks for any help you can provide! Could this be a known issue? The stack includes Javascript and several other technologies. I'm open to any suggestions.