Merge 10.5 into 10.6

storage/innobase/srv/srv0srv.cc

@@ -1974,8 +1974,7 @@ void srv_purge_shutdown()
 		while(!srv_purge_should_exit()) {
 			ut_a(!purge_sys.paused());
 			srv_wake_purge_thread_if_not_active();
-			std::this_thread::sleep_for(
-				std::chrono::milliseconds(1));
+			purge_coordinator_task.wait();
 		}
 		purge_sys.coordinator_shutdown();
 		srv_shutdown_purge_tasks();