cache std::thread::hardware_concurrency() result at start up

project-tsurugi · Aug 13, 2024 · 244abdb · 244abdb
1 parent a562439
commit 244abdb
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/include/destroy_manager.h b/include/destroy_manager.h
@@ -14,7 +14,7 @@ class destroy_manager {
         std::size_t expected{
                 destroy_threads_num_.load(std::memory_order_acquire)};
         for (;;) {
-            if (expected >= std::thread::hardware_concurrency()) {
+            if (expected >= hardware_concurrency_) {
                 return false;
             }
             std::size_t desired = expected + 1;
@@ -34,6 +34,7 @@ class destroy_manager {
 
 private:
     static inline std::atomic<std::size_t> destroy_threads_num_{0}; // NOLINT
+    static inline std::size_t hardware_concurrency_{std::thread::hardware_concurrency()}; // NOLINT
 };
 
 } // namespace yakushima