State and Line Performance Improvements

bench/CMakeLists.txt

@@ -22,6 +22,7 @@ endfunction()
 
 add_bench(WaveBenchmark WaveBench.cpp)
 add_bench(MoordynBenchmark MDBench.cpp)
+add_bench(LinesBenchmark LinesBench.cpp)
 
 add_custom_target(run_benchmarks
     COMMAND $<TARGET_FILE:WaveBenchmark>

bench/LinesBench.cpp

@@ -0,0 +1,67 @@
+#include "LinesBench.hpp"
+#include "Time.hpp"
+#include <benchmark/benchmark.h>
+#include <sstream>
+
+/**
+ * @brief Benchmarks stepping the model 0.1s
+ * Loads the given model file and measures the duration
+ * to complete an 0.1 second outer time step.
+ * @param state Benchmark state
+ * @param tScheme name of integrator to use
+ */
+static void
+MoorDynStepWithIntegrator(benchmark::State& state, const std::string& tScheme)
+{
+	int num_lines = state.range(0);
+	int num_segments = state.range(1);
+	std::string input_file = "Mooring/cases/" + std::to_string(num_lines) +
+	                         "_lines_" + std::to_string(num_segments) +
+	                         "_segs/lines.txt";
+	moordyn::MoorDyn system(input_file.c_str(), MOORDYN_NO_OUTPUT);
+	system.SetDisableOutput(true);
+
+	// Don't have to free this pointer because it's done by the MoorDyn system.
+	moordyn::TimeScheme* timeScheme = moordyn::create_time_scheme(
+	    tScheme, system.GetLogger(), system.GetWaves());
+	system.SetTimeScheme(timeScheme);
+
+	// int err;
+	unsigned int n_dof;
+	n_dof = system.NCoupledDOF();
+	double *x = NULL, *dx = NULL;
+	if (n_dof) {
+		x = new double[n_dof];
+		std::fill(x, x + n_dof, 0.0);
+		dx = new double[n_dof];
+		std::fill(dx, dx + n_dof, 0.0);
+	}
+	system.Init(x, dx, true);
+
+	double t = 0.0, dt = 0.01;
+	double f[3];
+
+	for (auto _ : state) {
+		system.Step(x, dx, f, t, dt);
+	}
+	state.counters["OuterTimeStep"] = dt;
+}
+static void
+MoordynStepCaseRK4(benchmark::State& state)
+{
+	MoorDynStepWithIntegrator(state, "RK4");
+}
+BENCHMARK(MoordynStepCaseRK4)
+    ->ArgsProduct({ { 1, 2, 4, 8, 16, 32, 64 }, { 1, 2, 4, 8, 16, 32, 64 } })
+    ->Unit(benchmark::kMicrosecond);
+
+static void
+MoordynStepCaseRK2(benchmark::State& state)
+{
+	MoorDynStepWithIntegrator(state, "RK2");
+}
+BENCHMARK(MoordynStepCaseRK2)
+    ->ArgsProduct({ { 1, 2, 4, 8, 16, 32, 64 }, { 1, 2, 4, 8, 16, 32, 64 } })
+    ->Unit(benchmark::kMicrosecond);
+
+BENCHMARK_MAIN();

bench/LinesBench.hpp

@@ -0,0 +1,11 @@
+
+#pragma once
+
+#define _USE_MATH_DEFINES
+#include "MoorDyn.h"
+#include "MoorDyn2.hpp"
+#include "Waves.hpp"
+#include "Waves/SpectrumKin.hpp"
+
+#include <cmath>
+#include <iostream>

bench/MDBench.cpp

@@ -21,8 +21,10 @@ LineGetStateDeriv(benchmark::State& state, std::string input_file)
 
 	auto line = system.GetLines().front();
 
+	std::vector<moordyn::vec> vel{};
+	std::vector<moordyn::vec> acc{};
 	for (auto _ : state) {
-		line->getStateDeriv();
+		line->getStateDeriv(vel, acc);
 	}
 }
 BENCHMARK_CAPTURE(LineGetStateDeriv,

bench/Mooring/cases/.gitignore

@@ -0,0 +1 @@
+lines.txt

bench/Mooring/cases/generate_cases.py

@@ -0,0 +1,92 @@
+from itertools import product
+import os
+from dataclasses import dataclass
+
+"""Simple script for generating a bunch of model files for benchmarking purposes.
+
+Just needs basic python (tested for version >=3.8).
+"""
+
+
+@dataclass
+class BenchmarkParams:
+    num_lines: int
+    num_segments: int
+
+
+def generate_benchmark(base_output_folder, params: BenchmarkParams):
+    """Generate a single benchmark model file.
+
+    The model has a user defined number of lines that each share a fixed top
+    point, and have their own bottom point.
+    They start off at a 10 degree angle from vertical.
+    """
+    points = "\n".join(
+        f"{i + 2} free 34.20201433256687 0.0 -93.96926207859084 0 0 0 0 -"
+        for i in range(params.num_lines)
+    )
+    line_length = 100.0
+    lines = "\n".join(
+        f"{i+1} chain 1 {i + 2} {line_length} {params.num_segments} p,t"
+        for i in range(params.num_lines)
+    )
+
+    file_str = f"""--------------------- MoorDyn Input File -------------------------------------------------------
+Output from generate_cases.py
+----------------------- LINE TYPES --------------------------------------------------------------
+TypeName   Diam    Mass/m     EA         BA/-zeta    EI         Cd     Ca     CdAx    CaAx
+(name)     (m)     (kg/m)     (N)        (N-s/-)     (N-m^2)    (-)    (-)    (-)     (-)
+chain      0.252   390        16000000.0 -0.3        0.0        1.37   0.64   1.0     0.0
+----------------------- POINTS -------------------------------------------------------------------
+Node      Type      X        Y         Z        M        V         CdA    CA
+(-)       (-)       (m)      (m)       (m)      (kg)     (m^3)     (m^2)  (-)
+1         free      0.0      0.0       0.0      0        0         0      0 -
+{points}
+-------------------------- LINES -----------------------------------------------------------------
+Line     LineType NodeA     NodeB  UnstrLen  NumSegs     Flags/Outputs
+(-)      (-)       (-)       (-)   (m)         (-)          (-)
+{lines}
+-------------------------- SOLVER OPTIONS---------------------------
+0        writeLog     - Write a log file
+0.001 dtM          - time step to use in mooring integration
+rk4      tScheme
+3000000.0    kb           - bottom stiffness
+300000.0    cb           - bottom damping
+200.0    WtrDpth      - water depth
+4.0      ICDfac       - factor to scale drag coeff during IC
+1.5e-06    threshIC     - threshold for IC convergence
+0.0    TmaxIC       - threshold for IC convergence
+1e-05     dtIC        - Time lapse between convergence tests (s)
+9.81     g     - gravitational force constant
+1025     rho     - water density
+0     WaveKin     - waves mode
+0     Currents     - current mode
+------------------------- need this line --------------------------------------
+"""
+
+    folder_name = f"{params.num_lines}_lines_{params.num_segments}_segs"
+
+    output_folder = os.path.join(base_output_folder, folder_name)
+    try:
+        os.mkdir(output_folder)
+    except FileExistsError:
+        pass
+
+    out_path = os.path.join(output_folder, "lines.txt")
+
+    with open(out_path, "w") as f:
+        f.write(file_str)
+
+
+def main():
+
+    number_of_lines = [2**n for n in range(7)]
+    number_of_segments = [2**n for n in range(7)]
+
+    for vals in product(number_of_lines, number_of_segments):
+        params = BenchmarkParams(*vals)
+        generate_benchmark("./", params)
+
+
+if __name__ == "__main__":
+    main()