spring – rest service and grpc service performance

I have created service using rest api and grpc and I am using hibernate for backend. datasource is same just I want check how fast the grpc is as compared to rest api so I am fetching 5000 record from table which contains almost 200 column.so after fetching data in both rest and grpc. I have observed that both have almost same metrics
For rest api it take 20.50s
For grpc api it take 21.20s
I have tested using postman.
even grpc is little bit slow almost 1 sec I have used uranary in grpc. So I want to know in which way we can find the performance better as compared to rest api

I was expecting grpc would be faster but performance is almost same