The KScalar Simulator

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    11 Citations (Scopus)


    Modern processors increase their performance with complex microarchitectural mechanisms, which makes them more and more difficult to understand and evaluate. KScalar is a graphical simulation tool that facilitates the study of such processors. It allows students to analyze the performance behavior of a wide range of processor microarchitectures: from a very simple in-order, scalar pipeline, to a detailed out-of-order, superscalar pipeline with non-blocking caches, speculative execution, and complex branch prediction. The simulator interprets executables for the Alpha AXP instruction set: from very short program fragments to large applications. The object's program execution may be simulated in varying levels of detail: either cycle-by-cycle, observing all the pipeline events that determine processor performance, or million cycles at once, taking statistics of the main performance issues. Instructors may use KScalar in several ways. First, it may be used to provide demonstrations in lectures or online learning environments. Second, it allows students to investigate the characteristics of specific processor microarchitectures as practical short assignments associated to a lecture course. Third, students may undertake major projects involving the optimization of real programs at the software-hardware interface, or involving the optimization of a processor microarchitecture for a given application workload. A preliminary version of KScalar has been successfully used in several lecture courses during the last two years in the University Autónoma of Barcelona. It runs on a x86/Linux/KDE system. The graphical interface has been developed using the KDE and QT libraries. The simulator engine running behind the graphical interface is a heavily-modified version of SimpleScalar. KScalar code is available under the terms of the GNU and SimpleScalar General Public License Categories and Subject Descriptors: C.0 [Computer Systems Organization - General]: Modeling of Computer Architecture; C.4 [Computer Systems Organization - Performance of Systems]: Design Studies; I.6.5 [Simulation and Modeling]: Model Development; K.3.1 [Computers and Education]: Computer Uses in Education. © 2002, ACM. All rights reserved.
    Original languageEnglish
    Pages (from-to)73-116
    JournalACM Journal of Educational Resources in Computing (JERIC)
    Issue number1
    Publication statusPublished - 1 Mar 2002


    • Design
    • Education
    • Performance
    • pipelined processor simulator


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