“When dealing with real-time systems, the overhead of
interprocess communications (IPC) becomes important. The
formalized structures that are used in Linux for IPC can carry with
them a significant amount of overhead. This can create timing
problems for your applications. In this article, I’ll examine
two of the best IPC mechanisms available under Linux — FIFOs and
shared memory…”
“An alternative to FIFOs is shared memory, in which a portion of
physical memory is set aside for sharing between Linux and
real-time processes. In a nutshell, shared memory is a pool of
memory segments reserved at boot time. These segments may be mapped
into the address space of more than one application, allowing for
fast data sharing, data updates, and handshaking. This allows for
low-latency parallel updates.”