Optimizes hotpath resource reservation using upper bound for AabbTree…

…World
louis-langholtz · Oct 12, 2023 · 878b830 · 878b830
1 parent 352d716
commit 878b830
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Showing 3 changed files with 15 additions and 14 deletions.
diff --git a/Library/source/playrho/d2/AabbTreeWorld.cpp b/Library/source/playrho/d2/AabbTreeWorld.cpp
@@ -679,8 +679,9 @@ auto FindContacts(pmr::memory_resource& resource,
     -> std::vector<AabbTreeWorld::ProxyKey, pmr::polymorphic_allocator<AabbTreeWorld::ProxyKey>>
 {
     std::vector<AabbTreeWorld::ProxyKey, pmr::polymorphic_allocator<AabbTreeWorld::ProxyKey>> proxyKeys{&resource};
-    static constexpr auto DefaultReserveSize = 512u;
-    proxyKeys.reserve(DefaultReserveSize); // upper bound is current size of tree
+    // Never need more than tree.GetLeafCount(), but in case big, use smaller default...
+    static constexpr auto DefaultReserveSize = 256u;
+    proxyKeys.reserve(std::min(tree.GetLeafCount(), DefaultReserveSize));
 
     // Accumalate contact keys for pairs of nodes that are overlapping and aren't identical.
     // Note that if the dynamic tree node provides the body index, it's assumed to be faster

diff --git a/UnitTests/AabbTreeWorld.cpp b/UnitTests/AabbTreeWorld.cpp
@@ -260,12 +260,12 @@ TEST(AabbTreeWorld, GetResourceStatsWhenOn)
     Step(world, stepConf);
     stats = GetResourceStats(world);
     ASSERT_TRUE(stats.has_value());
-    EXPECT_GT(stats->blocksAllocated, oldstats->blocksAllocated);
-    EXPECT_GT(stats->bytesAllocated, oldstats->bytesAllocated);
-    EXPECT_GT(stats->maxBlocksAllocated, oldstats->maxBlocksAllocated);
-    EXPECT_GT(stats->maxBytesAllocated, oldstats->maxBytesAllocated);
-    EXPECT_GT(stats->maxBytes, oldstats->maxBytes);
-    EXPECT_GT(stats->maxAlignment, oldstats->maxAlignment);
+    EXPECT_EQ(stats->blocksAllocated, oldstats->blocksAllocated);
+    EXPECT_EQ(stats->bytesAllocated, oldstats->bytesAllocated);
+    EXPECT_EQ(stats->maxBlocksAllocated, oldstats->maxBlocksAllocated);
+    EXPECT_EQ(stats->maxBytesAllocated, oldstats->maxBytesAllocated);
+    EXPECT_EQ(stats->maxBytes, oldstats->maxBytes);
+    EXPECT_EQ(stats->maxAlignment, oldstats->maxAlignment);
 }
 
 TEST(AabbTreeWorld, CreateDestroyEmptyStaticBody)

diff --git a/UnitTests/World.cpp b/UnitTests/World.cpp
@@ -3749,10 +3749,10 @@ TEST(World, GetResourceStatsWhenOn)
     Step(world, stepConf);
     stats = GetResourceStats(world);
     ASSERT_TRUE(stats.has_value());
-    EXPECT_GT(stats->blocksAllocated, oldstats->blocksAllocated);
-    EXPECT_GT(stats->bytesAllocated, oldstats->bytesAllocated);
-    EXPECT_GT(stats->maxBlocksAllocated, oldstats->maxBlocksAllocated);
-    EXPECT_GT(stats->maxBytesAllocated, oldstats->maxBytesAllocated);
-    EXPECT_GT(stats->maxBytes, oldstats->maxBytes);
-    EXPECT_GT(stats->maxAlignment, oldstats->maxAlignment);
+    EXPECT_EQ(stats->blocksAllocated, oldstats->blocksAllocated);
+    EXPECT_EQ(stats->bytesAllocated, oldstats->bytesAllocated);
+    EXPECT_EQ(stats->maxBlocksAllocated, oldstats->maxBlocksAllocated);
+    EXPECT_EQ(stats->maxBytesAllocated, oldstats->maxBytesAllocated);
+    EXPECT_EQ(stats->maxBytes, oldstats->maxBytes);
+    EXPECT_EQ(stats->maxAlignment, oldstats->maxAlignment);
 }