a "pico kernel" [also known as cokernel, pico-kernel, nano-kernel or dual kernel (dk)] with the normal Linux kernel, operating between or in parallel with Linux and the hardware. Interrupts are intercepted by this pico kernel and directed to a real-time environment that is executing the latency critical applications. In the example of Xenomai, the pico kernel is called Cobalt, a small real-time infrastructure which schedules time-critical activities independently from the main kernel logic and communicates with remainder Linux processes through Portable Operating System Interface (POSIX) Application Programming Interface (APIs). See 2 for more information. PREEMPT_R adds predictable latency to execution of a standard Linux environment by converting Linux into a fully preemptible kernel. But the latency bound is very high, in the order of magnitude 10 us worst case latency between interrupt and corresponding user-space process execution time. Compared to an RTOS as deployed on a DSP (order of magnitude 1 us response time to an event), this can be a prohibiting execution of a typical DSP like Layer 1 framework. A third alternative is to use Linux as an OS, but don't rely on any os services directly by (for example) implementing all relevant drivers in a user-space environment as opposed to relying on the os to provide these services for you. This concept relies on a few provisions that Linux makes the ability to affine a core to a task. 188 Open Radio Access Network (O-RAN) Systems Architecture and Design the ability to set the priority of a User Space task to a level that prohibits other tasks (Kernel or User Space) from interrupting it. the ability to steer interrupts (from timers, IO, ) to a (sub)set of available cores. the ability to provide access to the relevant portion of the system memory map to be able to support custom driver development. Now, the application developer can design a proprietary and application-optimized "micro kernel" os to schedule different tasks within this application. In a way, it can