2-5 April 2019
Jardí Botànic de València
Europe/Zurich timezone

Speeding up Particle Track Reconstruction using a Vectorized and Parallelized Kalman Filter Algorithm: Recent Improvements and Applicability to the Software Trigger

4 Apr 2019, 10:00
Jardí Botànic de València

Jardí Botànic de València

Carrer Quart 80, 46008 València, Spain
Talk 6: Architectures and techniques for fast track reconstruction


Allison Reinsvold Hall (Fermilab)


Building particle tracks is the most computationally intense step of event reconstruction at the LHC. With the increased instantaneous luminosity and associated increase in pileup expected from the High-Luminosity LHC, the computational challenge of track finding and fitting requires novel solutions. The current track reconstruction algorithms used at the LHC are based on Kalman-filter methods that achieve good physics performance. By adapting the Kalman-filter techniques for use on many-core SIMD architectures such as the Intel Xeon and Intel Xeon Phi and (to a limited degree) NVIDIA GPUs, we are able to obtain significant speedups and comparable physics performance.

Recent work has focused on integrating the algorithm into the CMSSW environment for use in the CMS High Level Trigger during Run 3 of the LHC. New optimizations including the removal of hits from out-of-time pileup and improvements on the ranking of the hit candidates have further increased the speedup of the algorithm and improved the track-building efficiency. The use of advanced profiling techniques have identified additional areas to target for optimization. The current structure and performance of the code and future plans for the algorithm will be discussed.

Primary authors

Giuseppe Cerati (Fermi National Accelerator Lab. (US)) Peter Elmer (Princeton University (US)) Brian Gravelle (University of Oregon) Allison Reinsvold Hall (Fermilab) Matti Kortelainen (Fermi National Accelerator Lab. (US)) Slava Krutelyov (Univ. of California San Diego (US)) Steven R Lantz (Cornell University (US)) Mario Masciovecchio (Univ. of California San Diego (US)) Kevin McDermott (Cornell University (US)) Boyana Norris Daniel Sherman Riley (Cornell University (US)) Matevz Tadel (Univ. of California San Diego (US)) Peter Wittich (Cornell University (US)) Frank Wuerthwein (Univ. of California San Diego (US)) Avi Yagil (Univ. of California San Diego (US))

Presentation Materials

Peer reviewing