Associate professor

Department of Distributed and Dependable Systems
Faculty of Mathematics and Physics
Charles University, Czech Republic

Phone: +420 951 554 189


My primary research interests can be found in the areas of dynamic program analysis, and software performance evaluation and modeling. While the two areas may seem rather broad and too far apart, the topics that I work make them much closer. After all, software performance is about observing what applications do and measuring how fast they do it (easily, accurately, promptly — pick two), while dynamic program analysis is about … observing and analyzing what applications do.

With respect to dynamic program analysis, I am mostly concerned about analysis composition, program instrumentation, profiling accuracy, and observability of program execution on modern managed platorms. With respect to software performance, I mostly focus on methods and tools for increasing performance awareness during software project development. This calls for automatic performance evaluation during development, automating performance change detection, and testable documentation of assumptions about program performance.

I am also generally interested in object-oriented programming and design, programming languages and practices, operating systems, computer architectures, and other systems-related topics. I teach or have taught courses on some of those topics.




Publications (last five years)

Publication index at DBLP, Google Scholar profile.

L. Bulej, T. Bureš, A. Filandr, P. Hnětynka, I. Hnětynková, J. Pacovský, G. Sandor, I. Gerostathopoulos:
Managing latency in edge–cloud environment, in Journal of Systems and Software 172, 2021
DOI: 10.1016/j.jss.2020.110872
L. Bulej, V. Horký, P. Tůma:
Tracking Performance of Graal on Public Benchmarks, presented at Science, Art, Magic: Using and Developing The Graal Compiler, 2021
L. Bulej, T. Bureš, P. Hnětynka, V. Čamra, P. Siegl, M. Töpfer:
IVIS: Highly customizable framework for visualization and processing of IoT data, in Proceedings of EUROMICRO SEAA 2020, Portorož, Slovenia, 2020
DOI: 10.1109/SEAA51224.2020.00095
L. Bulej, V. Horký, P. Tůma, F. Farquet, A. Prokopec:
Duet Benchmarking: Improving Measurement Accuracy in the Cloud, in Proceedings of the ACM/SPEC International Conference on Performance Engineering, pp. 100–107, 2020
ISBN: 978-1-4503-6991-6, DOI: 10.1145/3358960.3379132
L. Bulej, V. Horký, P. Tůma:
Initial Experiments with Duet Benchmarking: Performance Testing Interference in the Cloud, in Proc. 27th IEEE Intl. Symposium on Modeling, Analysis, and Simulation of Computer and Telecommunication Systems (MASCOTS), pp. 249-255, 2019
DOI: 10.1109/MASCOTS.2019.00035
A. Prokopec, A. Rosà, D. Leopoldseder, G. Duboscq, P. Tůma, M. Studener, L. Bulej, Y. Zheng, A. Villazón, D. Simon, T. Würthinger, W. Binder:
Renaissance: A Modern Benchmark Suite for Parallel Applications on the JVM (Extended Abstract), in Companion Proc. ACM SIGPLAN Conference on Systems, Programming, Languages, and Applications: Software for Humanity (SPLASH), pp. 11–12, 2019
ISBN: 978-1-4503-6992-3, DOI: 10.1145/3359061.3362778
A. Prokopec, A. Rosà, D. Leopoldseder, G. Duboscq, P. Tůma, M. Studener, L. Bulej, Y. Zheng, A. Villazón, D. Simon, T. Würthinger, W. Binder:
Renaissance: Benchmarking Suite for Parallel Applications on the JVM, in Proc. 40th ACM SIGPLAN Conference on Programming Language Design and Implementation (PLDI), pp. 17, 2019
DOI: 10.1145/3314221.3314637
I. Gerostathopoulos, C. Prehofer, L. Bulej, T. Bureš, V. Horký, P. Tůma:
Cost-Aware Stage-Based Experimentation: Challenges and Emerging Results, in 2018 IEEE International Conference on Software Architecture Companion (ICSA-C), pp. 72-75, 2018
DOI: 10.1109/ICSA-C.2018.00027
P. Kubát, L. Bulej, T. Bureš, V. Horký, P. Tůma:
Adaptive Dispatch: A Pattern for Performance-Aware Software Self-Adaptation, in Companion Proc. 9th ACM/SPEC Intl. Conf. on Performance Engineering (ICPE), pp. 195-198, 2018
ISBN: 978-1-4503-5629-9, DOI: 10.1145/3185768.3186406
L. Bulej, V. Horký, P. Tůma:
Do We Teach Useful Statistics for Performance Evaluation?, in Companion Proc. 8th ACM/SPEC on Intl. Conf. on Performance Engineering, pp. 185–189, 2017
ISBN: 978-1-4503-4899-7, DOI: 10.1145/3053600.3053638
P. Stefan, V. Horký, L. Bulej, P. Tůma:
Unit Testing Performance in Java Projects: Are We There Yet?, in Proc. 8th ACM/SPEC Intl. Conf. on Performance Engineering (ICPE), pp. 401–412, 2017
ISBN: 978-1-4503-4404-3, DOI: 10.1145/3030207.3030226
L. Bulej, T. Bureš, V. Horký, J. Kotrč, L. Marek, T. Trojánek, P. Tůma:
Unit testing performance with Stochastic Performance Logic, in Automated Software Engineering 24(1), pp. 139-187, 2017
DOI: 10.1007/s10515-015-0188-0
Y. Zheng, L. Bulej, W. Binder:
An Empirical Study on Deoptimization in the Graal Compiler, in Proc. 31st European Conference on Object-Oriented Programming (ECOOP), pp. 1–30, 2017
ISBN: 978-3-95977-035-4, DOI: 10.4230/LIPIcs.ECOOP.2017.30