[no subject]

On one hand we got shared memory plus locking for synchronization and
on the other hand message passing implemented in shared memory.
Shared memory is just a bulk of memory without any predivined structure.
Message passing is a protocol that defines the communication between
processes/subsystems.
A protocol is alot more stricter than just a bulk of memory.
It limits the freedom but prevents chaos.
If everything would work perfect a protocol might be only overhead,
but if only one component is just not as perfect as the rest a protocol is
needed.
A protocol standardize things, that make it easier to debug and optimize
communication
and most important, you can predict the behavior of system.
Any subsystem can communicate with an other subsystem.

What I miss in alot of plans is a distributed point of view.
It's always one cpu or more cpu's in one machine,
but what if we want to use a cluster of machines.
Message passing is the key.
It cannot be only implemented in shared memory but in for example network
messages.

The moral of the story is:
Messaging creates order in chaos.