Tests/Benchmarks/AtlasStepperBenchmark.cpp

0001 // This file is part of the Acts project.
0002 //
0003 // Copyright (C) 2017-2019 CERN for the benefit of the Acts project
0004 //
0005 // This Source Code Form is subject to the terms of the Mozilla Public
0006 // License, v. 2.0. If a copy of the MPL was not distributed with this
0007 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
0008
0009 #include "Acts/Definitions/Units.hpp"
0010 #include "Acts/EventData/ParticleHypothesis.hpp"
0011 #include "Acts/EventData/TrackParameters.hpp"
0012 #include "Acts/Geometry/GeometryContext.hpp"
0013 #include "Acts/MagneticField/ConstantBField.hpp"
0014 #include "Acts/MagneticField/MagneticFieldContext.hpp"
0015 #include "Acts/Propagator/AtlasStepper.hpp"
0016 #include "Acts/Propagator/Propagator.hpp"
0017 #include "Acts/Tests/CommonHelpers/BenchmarkTools.hpp"
0018 #include "Acts/Utilities/Logger.hpp"
0019
0020 #include <iostream>
0021
0022 #include <boost/program_options.hpp>
0023
0024 namespace po = boost::program_options;
0025 using namespace Acts;
0026 using namespace Acts::UnitLiterals;
0027
0028 int main(int argc, char* argv[]) {
0029   unsigned int toys = 1;
0030   double ptInGeV = 1;
0031   double BzInT = 1;
0032   double maxPathInM = 1;
0033   unsigned int lvl = Acts::Logging::INFO;
0034   bool withCov = true;
0035
0036   // Create a test context
0037   GeometryContext tgContext = GeometryContext();
0038   MagneticFieldContext mfContext = MagneticFieldContext();
0039
0040   try {
0041     po::options_description desc("Allowed options");
0042     // clang-format off
0043   desc.add_options()
0044       ("help", "produce help message")
0045       ("toys",po::value<unsigned int>(&toys)->default_value(20000),"number of tracks to propagate")
0046       ("pT",po::value<double>(&ptInGeV)->default_value(1),"transverse momentum in GeV")
0047       ("B",po::value<double>(&BzInT)->default_value(2),"z-component of B-field in T")
0048       ("path",po::value<double>(&maxPathInM)->default_value(5),"maximum path length in m")
0049       ("cov",po::value<bool>(&withCov)->default_value(true),"propagation with covariance matrix")
0050       ("verbose",po::value<unsigned int>(&lvl)->default_value(Acts::Logging::INFO),"logging level");
0051     // clang-format on
0052     po::variables_map vm;
0053     po::store(po::parse_command_line(argc, argv, desc), vm);
0054     po::notify(vm);
0055
0056     if (vm.count("help") != 0u) {
0057       std::cout << desc << std::endl;
0058       return 0;
0059     }
0060   } catch (std::exception& e) {
0061     std::cerr << "error: " << e.what() << std::endl;
0062     return 1;
0063   }
0064
0065   ACTS_LOCAL_LOGGER(
0066       getDefaultLogger("ATLAS_Stepper", Acts::Logging::Level(lvl)));
0067
0068   // print information about profiling setup
0069   ACTS_INFO("propagating " << toys << " tracks with pT = " << ptInGeV
0070                            << "GeV in a " << BzInT << "T B-field");
0071
0072   using BField = ConstantBField;
0073   using Stepper = AtlasStepper;
0074   using Propagator = Propagator<Stepper>;
0075   using Covariance = BoundSquareMatrix;
0076
0077   auto bField =
0078       std::make_shared<BField>(Vector3{0, 0, BzInT * UnitConstants::T});
0079   Stepper stepper(std::move(bField));
0080   Propagator propagator(std::move(stepper));
0081
0082   PropagatorOptions<> options(tgContext, mfContext);
0083   options.pathLimit = maxPathInM * UnitConstants::m;
0084
0085   Vector4 pos4(0, 0, 0, 0);
0086   Vector3 dir(1, 0, 0);
0087   Covariance cov;
0088   // clang-format off
0089   cov << 10_mm, 0, 0, 0, 0, 0,
0090          0, 10_mm, 0, 0, 0, 0,
0091          0, 0, 1, 0, 0, 0,
0092          0, 0, 0, 1, 0, 0,
0093          0, 0, 0, 0, 1_e / 10_GeV, 0,
0094          0, 0, 0, 0, 0, 0;
0095   // clang-format on
0096
0097   std::optional<Covariance> covOpt = std::nullopt;
0098   if (withCov) {
0099     covOpt = cov;
0100   }
0101   CurvilinearTrackParameters pars(pos4, dir, +1 / ptInGeV, covOpt,
0102                                   ParticleHypothesis::pion());
0103
0104   double totalPathLength = 0;
0105   std::size_t numSteps = 0;
0106   std::size_t numIters = 0;
0107   const auto propagationBenchResult = Acts::Test::microBenchmark(
0108       [&] {
0109         auto r = propagator.propagate(pars, options).value();
0110         if (totalPathLength == 0.) {
0111           ACTS_DEBUG("reached position "
0112                      << r.endParameters->position(tgContext).transpose()
0113                      << " in " << r.steps << " steps");
0114         }
0115         totalPathLength += r.pathLength;
0116         numSteps += r.steps;
0117         ++numIters;
0118         return r;
0119       },
0120       1, toys);
0121
0122   ACTS_INFO("Execution stats: " << propagationBenchResult);
0123   ACTS_INFO("average path length = " << totalPathLength / numIters / 1_mm
0124                                      << "mm");
0125   ACTS_INFO("average number of steps = " << 1.0 * numSteps / numIters);
0126
0127   return 0;
0128 }