Changing default allocation size in `channel/mod.rs`

I am creating a large dataflow graph with ~10000 nodes. It works great, except that I noticed that the static memory footprint of the program (before I feed any data to it) keeps growing as the graph gets bigger. I think it is currently in the order of a 100MB. This does not sound too bad, but my application creates thousands of instances of the dataflow, at which point this overhead becomes significant, and in fact dominates the memory footprint of the program. It appears that the main contributor are the buffers of size Message::default() (currently equal to 1024), pre-allocated for all channels. Is there a way to change this default without forking the repo?

Start in channel/mod.rs and inspect how Message::default() determines the pre-allocated channel buffer size. Trace where that default is used when channels are created, then check existing tests around channel allocation if present. Done means the allocation size can be changed without forking the repository and the behavior is covered by an appropriate test.