[pmarreck]

> I don't know how effective it is to chuck around 8MB data structures via message-passing.

It's my understanding that above a certain size and within the same running Erlang VM (machine), a reference is passed instead of a full copy.

[di4na]

only for binaries. But if your matrix is mainly modified outside of erlang, it may make sense to only use it as an opaque binary inside.