Stefan Marr

Associate Professor (Senior Lecturer)
and Royal Society Industry Fellow

Stefan Marr I am working at the School of Computing at the University of Kent. My work focuses on programming language implementation techniques, complex concurrent systems, and tooling.

Much of work revolves around making interpreters faster, detecting and preventing concurrency bugs at run time, and use modern language runtime systems to provide programmers with better tooling.

For contact details see my page at the School of Computing.

Archive of posts from March 2013

Mar 10, 2013: Replacing plyr's ddply with data.table to improve an R script's performance

Since quite a while, I am using R as a scripting language to generate graphs to the benchmarking results of various experiments. Since we have a new 64 core machine at the lab, I happen to run into performance issues with scripts that process the benchmark results, because the number of measurements increased significantly and the plyr library I use was designed with ease of use in mind, instead of performance. Concretely, I was experiencing script runtimes of up to 25min for a data set with roughly 50.000 measurements.