- Used to be 2 channels per node, it is now one per node, which is the minimum
- Now both hard edges, conditional edges, entrypoint and conditional entrypoint all use the same channel to trigger a node
- Was O(n^2) due to individual channels created for every conditional edge, including the default cond edge created for Command
- Now using a single channel per node for all conditional edge / command triggers, reducing to linear complexity
- Improves run time on sequential(200) from 1.8s to 0.14s
This PR adds a "shallow" version of `PostgresSaver` checkpointer that
ONLY stores the most recent checkpoint and does NOT retain any history.
It is meant to be a light-weight drop-in replacement for the
PostgresSaver that supports most of the LangGraph persistence
functionality with the exception of time travel.
Nuno Campos