Cold start times are a critical performance metric for serverless applications, where functions may need to initialize frequently. Here's how Bun and Node.js compare in this regard:
Cold Start Times
- Node.js: The median cold start time for a "Hello World" function is approximately 290 milliseconds. This relatively quick initialization is aided by optimizations in serverless environments, particularly on platforms like AWS Lambda, where Node.js is widely used and optimized[2][3].
- Bun: In contrast, Bun's median cold start time is significantly longer at around 750 milliseconds. This increased latency can be a disadvantage in serverless contexts where rapid initialization is crucial[2][3]. The longer cold start times for Bun are attributed to its current lack of optimization for serverless environments and the need for repeated downloads of the runtime[3].
Summary
Overall, Node.js demonstrates superior cold start performance compared to Bun, making it a more suitable choice for applications that require quick response times upon initialization. Bun, while promising in other areas such as CPU-bound tasks and overall performance, still has room for improvement regarding its cold start times in serverless applications[1][2][3].
Citations:[1] https://dev.to/kostyatretyak/a-quick-overview-of-buns-basic-features-and-a-comparison-with-nodejs-3o1a
[2] https://www.dreamhost.com/blog/bun-vs-node/
[3] https://5ly.co/blog/bun-vs-node-comparison/
[4] https://www.educative.io/answers/bun-vs-nodejs-a-comparative-analysis
[5] https://www.linkedin.com/pulse/nodejs-vs-bun-10-javascript-runtime-rumble-arbisoft
[6] https://refine.dev/blog/bun-js-vs-node/
[7] https://www.builder.io/blog/bun-vs-node-js
[8] https://www.reddit.com/r/node/comments/16e19xi/why_bun_is_so_much_faster_then_node/