Please contact the respective supervisor in case of questions for a specific topic. Further topics can usually be found through direct contact with our group members. We are open to new ideas - send your own topics to one of our members or a mailing list (for projects, theses, and internships).
Topics for theses
The following open topics are currently offered for Bachelor, Master and Diploma theses (click for details).
Database Topics
NVM-optimized Bepsilon-tree
Supervisor:
Sajad Karim
Abstract:
Non-volatile memory (NVM) is a new class in the traditional storage hierarchy. The technologies in this class share the characteristics of primary and secondary storage. They provide access latency close to DRAM, are addressable from cache lines, offer much higher capacity than DRAM, and are non-volatile. NVM is also often referred to as a disruptive memory technology as it has invalidated the traditional programming paradigm because, contrary to the traditional model, where data structures are generally categorized into memory and storage resident data structures, NVM-bound data structures cover both the aspects and the linked intricacies. Moreover, there has been considerable research made to leverage the characteristics of NVM, and in particular to the task mentioned in this posting, several designs for the index structures (e.g. wB+-Tree, NV-Tree, FP-Tree, LB+-Tree) [4, 5, 6, 7] that are typical to key-value storage engines are presented. However, one of the key aspects that is not addressed in the mentioned literature is they do not consider the heterogeneity of the modern storage landscape. For example, they all present NVM-DRAM optimized B-trees and do not consider block devices like SSD and HDD. Furthermore, and to the best of our knowledge, no research has been made to optimize Bepsilon-tree [1, 2, 3] for NVM despite the fact it offers similar scan operations as other B-tree variants yet its inserts and deletes are an order of magnitude faster.
Goals and results:
The goal is to implement an NVM-optimized Bepsilon-tree. It includes reviewing the recent literature and proposing data structures for the internal and leaf nodes in the B?-tree that would leverage the characteristics of NVM. Moreover, our server is equipped with the NVM module from Intel® (Intel® Optane™ DC Persistent Memory Modules), therefore, the proposed layouts should consider the characteristics of the module [8]. For example, the read and write latencies of the module are asymmetric where the reads are faster than the writes. Lastly, the proposed design has to be evaluated against the typical DRAM-based and disk-based Bepsilon-trees.
[1] Rudolf Bayer and Edward McCreight. 1970. Organization and Maintenance of Large Ordered Indices. In Proceedings of the ACM SIGFIDET (now SIGMOD) Workshop on Data Description, Access and Control (Houston, Texas). Association for Computing Machinery, New York, NY, USA, 107–141.
[2] Gerth et al. 2003. Lower bounds for external memory dictionaries.. In SODA, Vol. 3. 546–554.
[3] Michael A Bender, Martin Farach-Colton, William Jannen, Rob Johnson, Bradley C Kuszmaul, Donald E Porter, Jun Yuan, and Yang Zhan. 2015. An Introduction to B? -trees and Write-Optimization. login; magazine 40, 5
[4] Shimin Chen and Qin Jin. 2015. Persistent B+-trees in non-volatile main memory. Proc. VLDB Endow. 8, 7 (February 2015), 786–797.
[5] FPTree: A Hybrid SCM-DRAM Persistent and Concurrent B-Tree for Storage Class Memory.
[6] Jihang Liu, Shimin Chen, and Lujun Wang. 2020. LB+Trees: optimizing persistent index performance on 3DXPoint memory. Proc. VLDB Endow. 13, 7 (March 2020), 1078–1090.
[7] Y. Zhou, T. Sheng and J. Wan, "HBTree: an Efficient Index Structure Based on Hybrid DRAM-NVM," 2021 IEEE 10th Non-Volatile Memory Systems and Applications Symposium (NVMSA), Beijing, China, 2021, pp. 1-6, doi: 10.1109/NVMSA53655.2021.9628870.
[8] Lessons learned from the early performance evaluation of Intel optane DC persistent memory in DBMS. 10.1145/3399666.3399898
Software Engineering Topics
Advanced Topics in Feature-Model Analysis
Supervisor:
Elias Kuiter
Abstract:
This is an overview of thesis topics and software projects concerned with feature-model analysis. To work on one of these topics or projects, you must have successfully participated in our lecture on software product lines.
In the first lecture, several topics are presented for students to work on during the semester.
Software Projects
Currently, we offer the following topics for software projects:
Advanced Topics in Feature-Model Analysis
Supervisor:
Elias Kuiter
Abstract:
This is an overview of thesis topics and software projects concerned with feature-model analysis. To work on one of these topics or projects, you must have participated in our lecture on software product lines.
