SERVER-38739 Reduce iterations in lru_cache_test StressTest if iterator debugging is on. The destructor becomes O(n^2)

1 files changed, 9 insertions, 1 deletions

diff --git a/src/mongo/util/lru_cache_test.cpp b/src/mongo/util/lru_cache_test.cpp
index 70cb618d1c2..af3f5c9e208 100644
--- a/src/mongo/util/lru_cache_test.cpp
+++ b/src/mongo/util/lru_cache_test.cpp
@@ -215,7 +215,16 @@ TEST(LRUCacheTest, SizeZeroCache) {
 
 // Test a very large cache size
 TEST(LRUCacheTest, StressTest) {
+// If iterator debugging is on the LRU Cache destructor may be O(n^2). Reduce the max iteration size
+// to handle this.
+#if _MSC_VER && _ITERATOR_DEBUG_LEVEL >= 2
+    const int maxSize = 10000;
+    std::array<int, 3> sample{1, 34, 400};
+#else
     const int maxSize = 1000000;
+    std::array<int, 5> sample{1, 34, 400, 12345, 999999};
+#endif
+
     LRUCache<int, int> cache(maxSize);
 
     // Fill up the cache
@@ -227,7 +236,6 @@ TEST(LRUCacheTest, StressTest) {
     assertEquals(cache.size(), size_t(maxSize));
 
     // Perform some basic functions on the cache
-    std::array<int, 5> sample{1, 34, 400, 12345, 999999};
     for (auto s : sample) {
         auto found = cache.find(s);
         assertEquals(found->second, s);