AWS Lambda Cold Start Times
filia-aleks.medium.com
AWS Lambda Cold Start Times
1–10 of 233 posts
Re: AWS Lambda Cold Start Times
#2Cool article, but shouldn’t Amazon be providing this kind of info? Surely they have this data internally.
Re: AWS Lambda Cold Start Times
#3Nice to have some updated data and comparisons. This article doesn't include the effect if the Lambda has to connect to a VPC though, which adds time for the ENI. Though that was greatly improved in 2019-2020: https://aws.amazon.com/blogs/compute/announcing-improved-vpc...
Re: AWS Lambda Cold Start Times
#4At my last job we built an entire API on top of serverless. One of the things we had to figure out was this cold start time. If a user were to hit an endpoint for the first time, it would take 2x as long as it normally would at first. To combat this we wrote a "runWarm" function that kept the API alive at all times.
Sure kind of defeats the purpose of serverless but hey, enterprise software.
Re: AWS Lambda Cold Start Times
#5We run a few .net core lambdas and a few things that make a big difference for latency. 1. pre-jit the package, this reduces cold start times as the JIT doesn't need to run on most items. Still does later to optimize some items. 2 is sticking to the new .net json seralizer. The reference code uses both the new and old newtsonsoft package. The old package has higher memory allocations as it doesn't make use of the Span type.
Re: AWS Lambda Cold Start Times
#6just the cold-start data:
https://gist.github.com/Aleksandr-Filichkin/925fce9d910e04d2...
mirror: https://scribe.rip/@filia-aleks/aws-lambda-battle-2021-perfo...
Re: AWS Lambda Cold Start Times
#7This is great work - thanks for putting this together. We recently got a request to add Rust support to ServerlessStack and looks like there's good reason to :)
Re: AWS Lambda Cold Start Times
#8At my last job we built an entire API on top of serverless. One of the things we had to figure out was this cold start time. If a user were to hit an endpoint for the first time, it would take 2x as long as it normally would at first. To combat this we wrote a "runWarm" function that kept the API alive at all times. Sure kind of defeats the purpose of serverless but hey, enterprise software.
> To combat this we wrote a "runWarm" function that kept the API alive at all times.
This doesn't really work like you'd expect and isn't recommended, as it only helps a particular use-case. The reason is that AWS Lambda will only keep a single instance of your function alive. That means if two requests come in at the same time, you'd see a cold start on one of those invocations.
Instead, you want to look at something like provisioned concurrency.
Re: AWS Lambda Cold Start Times
#9One thing I wish he included was .NET 5 - since that switched to using Docker images I would be very interested in the differences.
Re: AWS Lambda Cold Start Times
#10At my last job we built an entire API on top of serverless. One of the things we had to figure out was this cold start time. If a user were to hit an endpoint for the first time, it would take 2x as long as it normally would at first. To combat this we wrote a "runWarm" function that kept the API alive at all times. Sure kind of defeats the purpose of serverless but hey, enterprise software.
Is there any guarantee of maximum startup time, or is there some upper timeout bound that you always have to anticipate in the worst case?