For local activity, the input doesn't contribute to history size but the output does, is this expected?

Community Support
1

If the workflow executes a local activity giving it say 10 MB data, it’s not recorded in the history and everything’s fine. I can’t see any inputs to that local activity in temporal UI too. However if that local activity returns data, it’s recorded in history (or at-least the temporal ui shows it AND it affects the history size). So if I return 10 MB from local activity, the workflow errors out saying max gRPC limit is 4 MBs.

Is this expected and can I rely on this (ie. pass unbounded-in-size data to local activity is fine as long as it doesn’t return anything big back to the workflow)?

2

Yes, this is expected. In some SDKs you can enable logging of local activity inputs. This might be useful for troubleshooting but counts towards all the limits.