1. 3

This is an educational OS designed to get students prepared to work on software aimed at parallel, distributed, multicore clusters. PIOS consists of a boot loader, a microkernel, a user-space runtime embedded in a minimal C library, and a set of sample applications, all sliced into subsets forming an instructional curriculum as described below. The microkernel itself only has four system calls. The course also covers weakly-consistent, state replication and distributed, shared memory.