Engineering

Publication Search Results

Now showing 1 - 10 of 203

  • (1999) Schumacher, J; Altermatt, Pietro P.; Heiser, Gernot; Aberle, Armin G.
    Conference Paper

  • (1999) Deller, L; Heiser, Gernot
    Conference Paper
    Linking and loading are the final steps in preparing a program for execution. This paper assesses issues concerning dynamic and static linking in traditional as well as single-address-space operating systems (SASOS). Related loading issues are also addressed. We present the dynamic linking model implemented in the Mungi SASOS and discuss its strengths and limitations. Benchmarking shows that dynamic linking in Mungi carries less overhead than dynamic linking in SGI`s Irix operating system


  • (1999) Altermatt, Peter; Sinton, Ron; Heiser, Gernot
    Conference Paper


  • (1998) Corkish, Richard; Sproul, Alistair; Puzzer, Tom; Altermatt, Peter; Heiser, Gernot; Luke, Keung
    Conference Paper

  • (1998) Bradley, Peter; Rozenfeld, Anatoly; Lee, Kevin; Jamieson, Dana; Heiser, Gernot; Satoh, S
    Journal Article
    The first results obtained using a SOI device for microdosimetry applications are presented. Microbeam and broadbeam spectroscopy methods are used for determining minority carrier lifetime and radiation damage constants. A spectroscopy model is presented which includes the majority of effects that impact spectral resolution. Charge collection statistics were found to substantially affect spectral resolution. Lateral diffusion effects significantly complicate charge collection

  • (1998) Heiser, Gernot; Elphinstone, Kevin; Vochteloo, J; Russell, Stephen; Liedtke, Jochen
    Journal Article
    Single-address-space operating systems (SASOS) are an attractive model for making the best use of the wide address space provided by the latest generations of microprocessors. SASOS remove the address space boundaries which make data sharing between processes difficult and expensive in traditional operating systems. They offer the potential of significant performance advantages for applications where sharing is important, such as object-oriented databases or persistent programming systems. We have built the Mungi system to demonstrate that a SASOS can offer these performance advantages without resorting to special hardware. Mungi is a very `pure` SASOS, featuring an unintrusive protection model based on sparse capabilities, a fast protected procedure call mechanism, and uses shared memory as the exclusive inter-process communication mechanism, as well as for I/O. The simplicity of our model makes it easy to implement it efficiently on conventional architectures. Our implementation of Mungi for the MIPS R4600 64-bit microprocessor is presented, which is based on our port of the L4 microkernel. Mungi is shown to outperform, in some instances by more than an order of magnitude, two UNIX operating systems, Irix and Linux, in several important operations, such as task creation and inter-process communications, and on the OO1 object-oriented database benchmark. As well, we describe how our approach to key issues in SASOS design provides better performance than other systems, such as Opal. Our experience shows that the SASOS concept is viable, and that a well-designed microkernel is an excellent base on which to build high-performance operating systems.

  • (1997) Altermatt, Pietro; Heiser, Gernot; Kiesewetter, Tobias; McIntosh, Keith; Honsberg, Christiana; Wenham, Stuart; Green, Martin
    Conference Paper
    An accurate numerical model is established for the simulation of buried contact cells in two dimensions. The physical parameters and the approximations are discussed as well as the procedures that lead to the foundations of the model. The model is applied to bifacial cells with three different rear surface configurations: (A) passivated by a thermally grown oxide, (B) by a dopand-induced floating junction, and (C) with a contacted junction. Especially when the cell is situated in a light-concentrating roof tile, configuration C performes far better than A and B. The two-dimensional effects of resistive losses in the semiconductor region of the cell are also discussed