Jonathan Chew

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This paper describes the design and implementation of virtual memory management within the CMU Mach Operating System and the experiences gained by the Mach kernel group in porting that system to a variety of architectures. As of this writing, Mach runs on more than half a dozen uniprocessors and multiprocessors including the VAX family of uniprocessors and(More)
Mach is a multiprocessor operating system being implemented at Carnegie-Mellon University. An important component of the Mach design is the use of memory objects which can be managed either by the kernel or by user programs through a message interface. This feature allows applications such as transaction management systems to participate in decisions(More)
Recent technological advances in memory management architectures, multiprocessor systems, and software architectures dictate a reevaluation of the virtual memory management support provided by an operating system. The problems posed by multiprocessor systems and the portability issues raised by the large variety of memory management units available have not(More)
This paper reports on an ongoing project to develop a general understanding of the problems encountered when building emulators for various operating systems at the user-level on top of a Mach 3.0 micro-kernel, and to propose a common framework to construct emulations for a wide range of target systems and environments. It presents an overview and(More)
Runtime characteristics of individual threads (such as IPC, cache usage, etc.) are a critical factor in making efficient scheduling decisions in modern chip-multiprocessor systems. They provide key insights into how threads interact when they share processor resources, and affect the overall system power and performance efficiency. In this paper, we propose(More)
Extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae are often susceptible in vitro to β-lactam/β-lactamase inhibitor (BLBLI) combination antibiotics, but their use has been limited by concerns of clinical inefficacy. We aimed to compare outcomes between patients treated with BLBLIs and carbapenems for bloodstream infection (BSI) caused by(More)
Aaltonen, Lauri A Aaronson, Neil Aaronson, Stuart Abbott, BL Abdel-Wahab, M Abe, Takashige Acero, Nuria Achen, Marc G Adachi, Yasushi Adamo, Sergio Adams, Richard Adriana, Albini Agalliu, Ilir Aggarwal, Amita Ahern, Roger Ajani, Jaffer Alberts, Steven R Alfirevic, Ana Allen, Naomi E Allgood, Prue C Allory, Yves Alonso, Javier Altevogt, P Altundang, Karim(More)
There is a trade-off between making space for future developments, and reducing interoperability and compatibility. We’ve attempted to make some decisions here, and explain our rationale. Most of the types are the scalar types from <sys/types.h>. These types are used in many fundamental system interfaces, so it’s important that we get this correct from the(More)
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