Lottery and stride scheduling : flexible proportional-share resource management

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Includes bibliographical references (p. 145-151).by Carl A. Waldspurger.Ph.D

USENIX Association Proceedings of the

Permission is granted for noncommercial reproduction of the work for educational or research purposes. This copyright notice must be included in the reproduced paper. USENIX acknowledges all trademarks herein. Memory Resource Management in VMware ESX Server VMware ESX Server is a thin software layer designed to multiplex hardware resources efficiently among virtual machines running unmodified commodity operating systems. This paper introduces several novel ESX Server mechanisms and policies for managing memory. A ballooning technique reclaims the pages considered least valuable by the operating system running in a virtual machine. An idle memory tax achieves efficient memory utilization while maintaining performance isolation guarantees. Content-based page sharing and hot I/O page remapping exploit transparent page remapping to eliminate redundancy and reduce copying overheads. These techniques are combined to efficiently support virtual machine workloads that overcommit memory.

A distributed computational economy for utilizing idle resources

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1989.Includes bibliographical references (leaves 89-93).by Carl A. Waldspurger.M.S

Lottery and Stride Scheduling: Flexible Proportional-Share Resource Management

This thesis presents flexible abstractions for specifying resource management policies, together with efficient mechanisms for implementing those abstractions. Several novel scheduling tech-niques are introduced, including both randomized and deterministic algorithms that provide proportional-share control over resource consumption rates. Such control is beyond the capa-bilities of conventional schedulers, and is desirable across a broad spectrum of systems that service clients of varying importance. Proportional-share scheduling is examined for several diverse resources, including processor time, memory, access to locks, and disk bandwidth. Resource rights are encapsulated by abstract, first-class objects called tickets. An active client consumes resources at a rate proportional to the number of tickets that it holds. Tickets can be issued in different amounts and may be transferred between clients. A modular currency abstraction is also introduced to flexibly name, share, and protect sets of tickets. Currencies can be used to isolate or group sets of clients, enabling the modular composition of arbitrary resource management policies. Two different underlying mechanisms are introduced to support these abstractions. Lotter

Preventing Recursion Deadlock in Concurrent Object-oriented Systems

This paper presents solutions to the problem of deadlock due to recursion in concurrent object-oriented programming languages. Two language-independent, system-level mechanisms for solving this problem are proposed: a novel technique using multi-ported objects, and a named-threads scheme that borrows from previous work in distributed computing. We compare the solutions and present an analysis of their relative merits