Add update and M scaling for benchmarks, save dt in cached

Author: ProExpertProg

cpp/bench/exps.cpp

@@ -7,18 +7,21 @@
 using namespace ahr;
 using namespace ahr::exp;
 template <space_like Exp> static void BM_ExpKXKY(benchmark::State &state) {
-  Dim const X = state.range(0);
-  Dim const Y = state.range(1);
+  Dim const M = state.range(0);
+  Dim const X = state.range(1);
+  Dim const Y = state.range(2);
 
-  Grid grid{1, X, Y};
+  Grid grid{M, X, Y};
   Real dt = 1.0;
   HyperCoefficients hyper = HyperCoefficients::calculate(dt, grid);
-
   Exp exp{grid};
-  exp.update(hyper, dt);
 
   for (auto _ : state) {
-    grid.for_each_kxky([&](Dim kx, Dim ky) { benchmark::DoNotOptimize(exp(kx, ky)); });
+    dt *= 1.2;
+    exp.update(hyper, dt);
+    for (int m = 0; m < M; ++m) {
+      grid.for_each_kxky([&](Dim kx, Dim ky) { benchmark::DoNotOptimize(exp(kx, ky)); });
+    }
   }
 }
 
@@ -32,37 +35,38 @@ template <moment_like Exp> static void BM_ExpM(benchmark::State &state) {
   HyperCoefficients hyper = HyperCoefficients::calculate(dt, grid);
 
   Exp exp{grid};
-  exp.update(hyper, dt);
 
   for (auto _ : state) {
+    dt *= 1.2;
+    exp.update(hyper, dt);
     for (Dim m = 0; m < M; ++m) {
       grid.for_each_kxky([&](Dim kx, Dim ky) { benchmark::DoNotOptimize(exp(m)); });
     }
   }
 }
 
 BENCHMARK_WMIN(BM_ExpKXKY<Eta>)
-    ->ArgsProduct({{2048, 4096, 8192}, {2048, 4096, 8192}})
+    ->ArgsProduct({{2, 4, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);
 BENCHMARK_WMIN(BM_ExpKXKY<Nu>)
-    ->ArgsProduct({{2048, 4096, 8192}, {2048, 4096, 8192}})
+    ->ArgsProduct({{2, 4, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);
 BENCHMARK_WMIN(BM_ExpKXKY<NuG>)
-    ->ArgsProduct({{2048, 4096, 8192}, {2048, 4096, 8192}})
+    ->ArgsProduct({{2, 4, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);
 BENCHMARK_WMIN(BM_ExpM<GM>)
-    ->ArgsProduct({{2, 4, 10}, {2048, 4096}, {2048, 4096}})
+    ->ArgsProduct({{4, 8, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);
 
 BENCHMARK_WMIN(BM_ExpKXKY<CachedKXKY<Eta>>)
-    ->ArgsProduct({{2048, 4096, 8192}, {2048, 4096, 8192}})
+    ->ArgsProduct({{2, 4, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);
 BENCHMARK_WMIN(BM_ExpKXKY<CachedKXKY<Nu>>)
-    ->ArgsProduct({{2048, 4096, 8192}, {2048, 4096, 8192}})
+    ->ArgsProduct({{2, 4, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);
 BENCHMARK_WMIN(BM_ExpKXKY<CachedKXKY<NuG>>)
-    ->ArgsProduct({{2048, 4096, 8192}, {2048, 4096, 8192}})
+    ->ArgsProduct({{2, 4, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);
 BENCHMARK_WMIN(BM_ExpM<CachedM<GM>>)
-    ->ArgsProduct({{2, 4, 10}, {2048, 4096}, {2048, 4096}})
+    ->ArgsProduct({{4, 8, 16}, {2048, 4096}, {2048, 4096}})
     ->Unit(benchmark::kMillisecond);

cpp/lib/CachedExponentials.hpp

@@ -22,9 +22,13 @@ concept updatable = requires(Exp exp, Real dt) {
 template <updatable Exp>
   requires space_like<Exp>
 struct CachedKXKY : Exp {
-  explicit CachedKXKY(Grid const &grid) : Exp(grid), factors(grid.KX, grid.KY) {}
+  explicit CachedKXKY(Grid const &grid) : Exp(grid), factors(grid.KX, grid.KY), dt(-1) {}
 
   void update(HyperCoefficients hyper, Real dt) {
+    // skip update if dt hasn't changed
+    if (this->dt == dt) { return; }
+    this->dt = dt;
+
     Exp::update(hyper, dt);
     this->grid.for_each_kxky([&](Dim kx, Dim ky) { factors(kx, ky) = Exp::operator()(kx, ky); });
   }
@@ -33,14 +37,19 @@ struct CachedKXKY : Exp {
 
 protected:
   Grid::Buf::R_XY factors; ///< Real but of size (KX,KY)
+  Real dt;
 };
 
 template <updatable Exp>
   requires moment_like<Exp>
 struct CachedM : Exp {
-  explicit CachedM(Grid const &grid) : Exp(grid), factors(grid.M) {}
+  explicit CachedM(Grid const &grid) : Exp(grid), factors(grid.M), dt(-1) {}
 
   void update(HyperCoefficients hyper, Real dt) {
+    // skip update if dt hasn't changed
+    if (this->dt == dt) { return; }
+    this->dt = dt;
+
     Exp::update(hyper, dt);
     for (Dim m = 0; m < this->grid.M; ++m) {
       factors[m] = Exp::operator()(m);
@@ -51,5 +60,6 @@ struct CachedM : Exp {
 
 protected:
   std::vector<Real> factors;
+  Real dt;
 };
 } // namespace ahr::exp