Open Projects

For Master's theses, Bachelor's theses or for Software Engineering projects in the Master's program

(Most topics can be adapted in scale to fit any of the above categories)


  • A Web-based Tool for doing Quizzes in Courses (Java, JavaScript)
    The goal of this project is to develop a web-based tool where a lecturer can ask questions and students can provide answers interactively via a notebook or a mobile. The answers should be immediately evaluated and visualized (individually or in summary). Question types should be multiple choice and free text (maybe also source code). For developing the tool, simplicity and responsiveness are more important than the number of features.

  • Low-Overhead Debugging with Sulong (Java)
    Sulong is an interpreter for LLVM IR, an intermediate representation of source code that can be produced by the Clang compiler for the C family of programming languages. It is based on the Truffle framework for implementing interpreters for programming languages and part of the GraalVM project. In addition to executing programs that were compiled to LLVM IR, Sulong also supports GraalVM's integrated debugging framework to allow users to debug these programs at source-level. At the moment, this debugging support is aimed at providing correct values for all possible symbols. This, however, comes at the cost of a significant run-time overhead since it prevents or even requires undoing several performance optimizations introduced by both Clang and GraalVM.
    The goal of this project is to implement an alternative performance mode for source-level debugging with Sulong. Instead of providing current values for all source-level symbols, in this mode the debugger should display only symbols whose values are still available despite optimizations. This will require analyzing the LLVM IR executed by Sulong and the debug information it contains. Once GraalVM's debugging framework has halted the running program and requests symbol information from it, the values referenced in the debug information can be compared against the current program state to determine which values are still available. For this project, no knowledge about compiler optimizations performed by either Clang or GraalVM is required.

  • Reference implementation of SOMns record and replay in GraaJS (Java)
    SOMns is a research language similar to Smalltalk. It provides specialised debugging support for its concurrency models, e.g. record & replay. Record and replay debugging is based on the idea of recording a program trace that allows one to deterministically reproduce an execution (including bugs). SOMns and GraalJS are both implemented in Java with the Truffle framework and use similar concurrency models. The goal of this thesis is to reimplement the record and replay strategy from SOMns in GraalJS. In addition, recording performance of the GraalJS implementation should be evaluated with benchmarks.

  • Enhancing the AcmeAir benchmark application
    AcmeAir is a simple web-application that represents the booking system of an airline. It is used to evaluate the run-time performance of debugging tools in our SOMns language implementation. Currently, AcmeAir supports a limited set of operations that are very database dependent. The goal of this project is to enhance AcmeAir with features one could find in a real booking system, for example multiple options for finding flight connections. Additionally, the JMeter configuration used to drive the benchmark needs to be updated to use the new features.

  • Test language interoperability between JavaScript and Ruby (JavaScript, some Ruby and Java)
    The Truffle Framework allows you to write code that interoperates between different languages. In this project, you should prepare test cases to see how well-behaving JavaScript is when executing on foreign (here: Ruby) objects. What happens when you try to execute methods from JavaScript's core library on Ruby objects? The project should result in a complete set of unit tests and an analysis of the failing behaviour.
    Contact: Dr. Wirth

  • NUMA support for the G1 Garbage Collector
    On multi-socket systems memory access time depends on the memory location relative to the processor (locality group): "closer" memory access latency is significantly smaller than memory that is located with a different processor. Currently G1 does not exploit this by improving or at least keeping access locality the same.
    Goals for this task could include implementation of the common heuristics used in literature that keep objects in the same locality group as long as possible, like a) let G1 keep data in the same locality group in the young generation and try to evenly spread data across locality groups in old generation; or b) try to keep locality in both young and old generation. Measure the impact of these strategies across a set of industry benchmarks and analyze other areas in the garbage collector that might benefit from NUMA awareness and potentially suggest changes.
    Contact: DI Schatzl