many small messages over kdbus

[Urs Fässler]

Hi all,
I need an IPC system which supports broadcasts. It would be nice if we
can send many small messages (~64 bytes every 5 ms to ~12 receiver).

On a BeagleBone @ 720 MHz (Linux 3.12, kdbus e62195ac as module) I get
nearly 100% CPU usage with the mentioned setup. Most time is spent in
kdbus, allocating and zeroing pages to deliver messages.

Now my questions are:
1. Are my results sane?
2. Is this a sane usage of kdbus or a kind of stupid idea?
3. Is it possible that the receiver provides a buffer for the messages,
   so that no allocation and zeroing is needed (or is it planned /
   welcome if someone implements it)?

Thanks
Urs