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My ahead-of-time JS engine Porffor eliminates JS cold starts on AWS Lambda. 12x faster and 2x cheaper than managed Node. Still very early but these results should speak for themselves :) goose.icu/lambda/

David Behroozi

@rootothez.bsky.social

15 Aug 2025

Do you have round-trip latency numbers? That would be a better measure of end user latency. Which distro of Llrt did you use, the one without the SDK?

Oliver Medhurst

@honk.foo

I used LLRT's Lambda release without the SDK. I tried round-trip latency but couldn't get good measurements, but I'm not an AWS person. I think duration is most important as this is specifically cold starts but happy to follow up.

15/8/25, 5:39 pm0 reposts2 likes

David Behroozi

@rootothez.bsky.social

15 Aug 2025

I use eventbridge to invoke a lambda every 8 minutes. The lambda is in the same region as the test functions. Lambdas are shutdown after inactivity of 7 minutes so this is allows me to measure coldstarts without using env variables which adds overhead. Details here: gist.github.com/perpil/4a056...

gist.github.comHow I measure E2E latency of lambdasHow I measure E2E latency of lambdas. GitHub Gist: instantly share code, notes, and snippets.