1. let each sandbox in the chain share the same request id. 2. fflush after fprintf

runtime/include/sandbox_functions.h

@@ -183,4 +183,5 @@ sandbox_print_perf(struct sandbox *sandbox)
 	        sandbox->module->name, sandbox->module->port, sandbox_state_stringify(sandbox->state),
 	        sandbox->module->relative_deadline_us, total_time_us, queued_us, initializing_us, runnable_us,
 	        running_us, blocked_us, returned_us, sandbox->linear_memory_size);
+	fflush(runtime_sandbox_perf_log);
 }

runtime/src/current_sandbox.c

@@ -114,6 +114,8 @@ current_sandbox_start(void)
 							   next_module->name, sandbox->client_socket_descriptor,
                                                            (const struct sockaddr *)&sandbox->client_address,
                                                            sandbox->request_arrival_timestamp, true, pre_func_output, output_length);
+                /* reset the request id to the same as the current request id */
+		sandbox_request->id = sandbox->id;  
 		/* Add to the Global Sandbox Request Scheduler */
                 global_request_scheduler_add(sandbox_request);
 		sandbox_remove_from_epoll(sandbox);

runtime/src/main.c

@@ -226,6 +226,7 @@ runtime_configure()
 		if (runtime_sandbox_perf_log == NULL) { perror("sandbox perf log"); }
 		fprintf(runtime_sandbox_perf_log, "id,function,state,deadline,actual,queued,initializing,runnable,"
 		                                  "running,blocked,returned,memory\n");
+		fflush(runtime_sandbox_perf_log);
 	} else {
 		printf("\tSandbox Performance Log: Disabled\n");
 	}