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It has been a decade since the ACM/IEEE CS2013 Curriculum guidelines recommended that all CS students learn about parallel and distributed computing (PDC). But few text- books for “core” CS courses–especially first-year courses–include coverage of PDC topics. To fill this gap, we have written free, online, beginner- and intermediate-level PDC textbooks, containing interactive C/C++ OpenMP, MPI, mpi4py, CUDA, and OpenACC code examples that students can run and modify directly in the browser. The books address a serious challenge to teaching PDC concepts, namely, easy access to the powerful hardware needed for observing patterns and scalability. This paper describes the content of these textbooks and the underlying infrastructure that make them possible. We believe the described textbooks fill a critical gap in PDC education and will be very useful for the community. 

Abstract topics such as recursion are challenging for many computer science students to understand. In this experience report, we explore function sonification—the addition of sound to a function to communicate information about the function’s behavior in real-time as it runs—as a pedagogical approach for improving students’ understanding of recursion. We present several example iterative and recursive function sonifications, plus spectrograms that illustrate their different sonic behaviors. We also present experimental evidence that using these sonifications significantly improved the understanding of recursion for students who used them, compared to students who used silent (i.e., traditional) versions of the same functions. Based on these experiences, we believe sonification has under-appreciated potential for teaching abstract computing topics. 

The Message Passing Interface (MPI) is a software platform that can utilize the parallel capabilities of most multi-processors, making it useful for teaching students about parallel and distributed computing (PDC). MPI provides language bindings for Fortran and C/C++, but many university instructors lack expertise in these languages, preventing them from using MPI in their courses. OpenMPI is a free implementation of MPI that also provides Java bindings, allowing instructors who know Java but not C/C++ or Fortran to teach PDC. However, Java has a reputation as a “slow” language, so some say it is unsuitable for teaching PDC. This paper gives a head-to-head comparison of the performance of OpenMPI's Java and C bindings. Our study shows that by default, Java can be faster than C unless one takes special measures, and it exhibits similar speedup, efficiency, and scalability. We conclude that Java is a suitable language for teaching PDC. 

Much work already exists on algorithm visualization—the graphical representation of an algorithm’s behavior—and its benefits for student learning. Visualization, however, offers limited benefit for students with visual impairments. This paper explores algorithm sonification—the representation of an algorithm’s behavior using sound. To simplify the creation of sonifications for modern algorithms, this paper presents a new Thread Safe Audio Library (TSAL). To illustrate how to create sonifications, the authors have added TSAL calls to four common sorting algorithm implementations, so that as the program accesses a value being sorted, the program plays a tone whose pitch is scaled to that value’s magnitude. In the resulting sonifications, one can (in real time) hear the behavioral differences of the different sorting algorithms as they run, and directly experience how fast (or slow) the algorithms sort the same sequence, compared to one another. This paper presents experimental evidence that the sonifications improve students’ long-term recall of the four sorting algorithms’ relative speeds. The paper also discusses other potential uses of sonification. 

The ACM/IEEE CS 2013 curriculum recommendations state that every undergraduate CS major should learn about parallel and distributed computing (PDC). One way to accomplish this is to teach students about the Message Passing Interface (MPI), a platform that is commonly used on modern supercomputers and Beowulf clusters, but can also be used on a Network of Workstations (NoW), or a multicore laptop or desktop. MPI incorporates many PDC concepts and can serve as a platform for hands-on learning activities in which students must apply those concepts. The MPI standard defines language bindings for Fortran and C/C++, but many university instructors lack expertise in these languages, preventing them from using MPI in their courses. OpenMPI is a free implementation of the MPI standard that also provides Java bindings for MPI. This paper describes how to install OpenMPI with these Java bindings; to illustrate the use of these bindings, the paper also presents several patternlets—minimalist example programs—that show how to implement PDC design patterns using OpenMPI and Java. This provides a new means of introducing students to PDC concepts. 

Classic synchronization problems are often used to introduce students to the subtleties of concurrency and synchronization mechanisms, such as semaphores, monitors, locks, and condition variables. The Dining Philosophers, Producers-Consumers, and Readers-Writers are all classic problems in which a correct solution requires the actions of multiple processes or threads to be synchronized. In this paper, we present visualizations for these three problems and describe their use as pedagogical tools to help students build accurate mental models of concurrency abstractions such as starvation, deadlock, livelock, and correct execution. We also present the results of an experiment that indicate students find using these visualizations to be significantly more engaging than reading a textbook, with no significant difference in learning. We do not claim that our visualizations should replace a course text; rather we present them as engaging pedagogical tools to complement the textbook in courses on Operating Systems, Programming Languages, and other courses where concurrency and synchronization are covered.