Serverless Execution Isolation

Question

I am looking at serverless architecture to process some customer data. The process itself is probably quite quick, but for various reasons I would like the cloud service provider to gurantee executional isolation. So far, I've talked to a rep from Amazon, who said that Amazon Lambda are not effectively isolated, and the lambda container may end up being reused.

Effectively, when running a function and, say, writing something to memory or disk (here we might not have control, as part of the solution would let customers execute arbitrary code) I would like a sandbox isolation gurantee.

I've read that Microsoft was going to offer such isolation, but apart from a news story, I couldn't find and concrete information. There they alude to extra costs of sandboxing functions for example.

So is there any provider that could gurantee executional isolation?

Answer 1

Apparently Google Cloud Functions is guaranteeing isolated execution:

Run in a fully-managed, serverless environment where Google handles infrastructure, operating systems, and runtime environments completely on your behalf. Each Cloud Function runs in its own isolated secure execution context, scales automatically, and has a lifecycle independent from other functions.

Emphasis mine