M-M/S-CD Memory Management: Conceptual and System Models

Abstract

M-M/S-CD (Master-Move/Slave-Clone:Destroy) is a conceptual memory management model that follows the minimality principle and it is specially designed for true microkernels. M-M/S-CD provides a minimal abstractions for management of both physical and virtual memory of computer system and creates a fundamental and well-isolated memory management layer over the Instruction Set Architecture (ISA) Abstraction Layer. Full set of user space memory management servers can be built on the basis of this memory management layer. Furthermore, the rest of the microkernel subsystems can be designed and implemented using M-M/S-CD as a foundation. Thus M-M/S-CD covers the kernel memory management alongside with user space memory management. In this paper, we discuss the conceptual model of M-M/S-CD and its system model, which highlights implementation details and its linkage with other kernel subsystems. We present the most important features of M-M/S-CD design, such as facilities provided for physical and virtual memory management, isolateness of the physical memory system, in-place memory accounting and more. We also discuss the various design decisions that influenced the implementation of these features on the IA-32 platform. We conclude by describing the current implementation status and plans in regard of M-M/S-CD.