[erlang-questions] message copying or by reference
Tue Jun 26 22:12:13 CEST 2007
Damien Morton wrote:
> When I send a message from one process to another on the same node, is
> that message passed by copying or by reference.
> Lets say I have an agent which is maintaining a largish internal state
> (i.e. several 10s ro 100s of KB when serialised) and wants to send a
> good portion of that to another process (i.e. if the state is thought of
> as a tree, then several subtrees might be sent). How is this handled?
The default Erlang/OTP system uses copying.
However, the distribution also comes with an (unsupported by Ericsson)
configuration where message sending happens mostly by passing a
reference. You can try this by starting the system as
There is also a relevant publication (*) where a related static analysis
and various tradeoffs of both configurations are discussed.
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