DataLoaderInstrumentation timingInstrumentation = new DataLoaderInstrumentation() {
            @Override
            public DataLoaderInstrumentationContext<DispatchResult<?>> beginDispatch(DataLoader<?, ?> dataLoader) {
                long then = System.currentTimeMillis();
                return DataLoaderInstrumentationHelper.whenCompleted((result, err) -> {
                    long ms = System.currentTimeMillis() - then;
                    System.out.println(format("dispatch time: %d ms", ms));
                });
            }
            @Override
            public DataLoaderInstrumentationContext<List<?>> beginBatchLoader(DataLoader<?, ?> dataLoader, List<?> keys, BatchLoaderEnvironment environment) {
                long then = System.currentTimeMillis();
                return DataLoaderInstrumentationHelper.whenCompleted((result, err) -> {
                    long ms = System.currentTimeMillis() - then;
                    System.out.println(format("batch loader time: %d ms", ms));
                });
            }
        };
        DataLoaderOptions options = DataLoaderOptions.newOptions().setInstrumentation(timingInstrumentation);
        DataLoader<String, User> userDataLoader = DataLoaderFactory.newDataLoader(userBatchLoader, options);