This is also done in the signal processors that power these systems. I don't know this system in particular, but the USN has been moving towards commodity comp

This is also done in the signal processors that power these systems. I don't know this system in particular, but the USN has been moving towards commodity computing hardware for these systems. Essentially, a rack of commercial servers (usually IBM) running stripped-down RHEL with a real-time kernel. The software for these systems is firm real-time, and generally uses the same principals as other real-time software (including, but not limited to, up-front allocation).