Migrating workloads - snapshot and restore somewhere else

[devigned]

Feature

When running a module with wasmtime, I would like to be able to capture the running memory of a workload, perhaps, while running, pause or stop the workload, move the workload elsewhere, then start the workload from where it left off.

Benefit

Being able to migrate a workload would enable workload state to be transferred to compute as the user of the workload is moving. Imagine someone driving down the highway and the workload traveling along edge compute with the user.

Implementation

Todo if the feature is interesting to the project.

Alternatives

One alternative is to externalize state from the module through some stateful service / component interface. However, this would require module developers to take a dependency on some service interface and rebuild applications to integrate with this external state store.

/cc @squillace

[bjorn3]

If the callstack is empty you can take an approach similar to wizer which doesn't require wasm engine support. If it isn't due to optimizations I can only see it working for the exact same compiled version of the wasm to native code. Wasm code calling into user provided functions calling back into wasm code is effectively impossible to snapshot I think.

[devigned]

Thank you for the pointer and quick reply, @bjorn3. I'm going to a bit of homework on wizer and post back.