FemtoLinux for seamless porting from RTOS to Linux
If you have a large monolithic VxWorks or other RTOS application that you wish to port to Linux FemtoLinux can make your life much easier. In the past, migrating such an application to Linux often meant complete architecture redesign in order to separate kernel mode code, i.e. drivers, from user mode code, i.e. applications on Linux. As FemtoLinux processes are very similar to RTOS tasks in that they run in kernel mode, it is now possible to keep the same architecture on both embedded Linux and RTOS.
FemtoLinux for increased performance
If you are scratching the limits of your CPU, which is often the case in embedded programming, FemtoLinux can help you increase performance. Some applications that frequently interact with the kernel, which most networking applications do, can get a huge performance boost by switching to FemtoLinux. For FemtoLinux processes, system call overhead is reduced to a simple function call, as opposed to an exception on standard Linux kernels. This optimization alone, which does not even require a recompilation of your application, can increase performance by up to 50%.
FemtoLinux performance optimizations are not limited to system call overhead reduction. With FemtoLinux it is possible to create zero copy applications, which is especially important for services that transfer large bulks of data to/from kernel. It also allows to reduce interrupt latency in some case.