We discuss an experiment aimed at lowering the operating system related overheads when performing small size message communications on a Beowulf class Linux PC cluster.
The experiment consists in adding a small number of new system calls to the Linux kernel allowing user code to send/receive messages to/from remote processes. The system calls have been implemented using the standard kernel module mechanism provided by Linux. Those new system calls allow small size messages to be exchanged between cluster nodes with times that are 10 to 15% smaller than those achieved using standard TCP/IP communications.