Add benchmark for update!

benchmarks/benchmarks.jl

@@ -1,4 +1,5 @@
 include("count_neighbors.jl")
 include("n_body.jl")
+include("update.jl")
 
 include("plot.jl")

benchmarks/update.jl

@@ -0,0 +1,43 @@
+using PointNeighbors
+using BenchmarkTools
+
+# For `perturb!`
+include("../test/point_cloud.jl")
+
+"""
+    benchmark_initialize(neighborhood_search, coordinates; parallel = true)
+
+Benchmark neighborhood search initialization with the given `coordinates`.
+"""
+function benchmark_initialize(neighborhood_search, coordinates; parallel = true)
+    return @belapsed $initialize!($neighborhood_search, $coordinates, $coordinates)
+end
+
+"""
+    benchmark_update_alternating(neighborhood_search, coordinates; parallel = true)
+
+A very simple benchmark for neighborhood search update, alternating between two differently
+perturbed point clouds.
+
+This is a good benchmark for incremental updates, since most particles stay in their cells.
+"""
+function benchmark_update_alternating(neighborhood_search, coordinates; parallel = true)
+    coordinates2 = copy(coordinates)
+    # Perturb all coordinates with a perturbation factor of `0.015`.
+    # This factor was tuned so that ~0.5% of the particles change their cell during an
+    # update in 2D and ~0.7% in 3D.
+    # These values are the same as the experimentally computed averages in 2D and 3D SPH
+    # dam break simulations. So this benchmark replicates a real-life SPH update.
+    perturb!(coordinates2, 0.015)
+
+    function update_alternating!(neighborhood_search, coordinates, coordinates2)
+        update!(neighborhood_search, coordinates, coordinates)
+        update!(neighborhood_search, coordinates, coordinates2)
+    end
+
+    result = @belapsed $update_alternating!($neighborhood_search, $coordinates,
+                                            $coordinates2)
+
+    # Return average update time
+    return 0.5 * result
+end

test/benchmarks.jl

@@ -13,5 +13,13 @@
         @testset verbose=true "`benchmark_n_body`" begin
             @test_nowarn_mod plot_benchmarks(benchmark_n_body, size, 2)
         end
+
+        @testset verbose=true "`benchmark_initialize`" begin
+            @test_nowarn_mod plot_benchmarks(benchmark_initialize, size, 2)
+        end
+
+        @testset verbose=true "`benchmark_update_alternating`" begin
+            @test_nowarn_mod plot_benchmarks(benchmark_update_alternating, size, 2)
+        end
     end
 end;