Here's a rehash of my comment on the blog which might cover this point:
From my experience, performance is a tough question to answer because you really have to think of the system as a whole. The weakest link (slowest piece) usually dictates the overall system perceived performance. Having a slow DB isn't going to make your choice of Java or Node.js matter that much...
So assuming that everything else is equal (like architecture, data structure choices, database driver quality, database design and queries, etc) it might be that Java is faster.. but it might be a moot point.
Writing asynchronous code in Node.js is much more convenient than Java and helps in doing more at the same time so that you aren't waiting for all those database queries to run one after the other, for example. Check out the Node.js async module for some cool patterns to use (https://github.com/caolan/async).
In all, I wouldn't make the choice to move to Node.js because it has better performance or not, but the overall holistic view.
From my experience, performance is a tough question to answer because you really have to think of the system as a whole. The weakest link (slowest piece) usually dictates the overall system perceived performance. Having a slow DB isn't going to make your choice of Java or Node.js matter that much...
So assuming that everything else is equal (like architecture, data structure choices, database driver quality, database design and queries, etc) it might be that Java is faster.. but it might be a moot point.
Writing asynchronous code in Node.js is much more convenient than Java and helps in doing more at the same time so that you aren't waiting for all those database queries to run one after the other, for example. Check out the Node.js async module for some cool patterns to use (https://github.com/caolan/async).
In all, I wouldn't make the choice to move to Node.js because it has better performance or not, but the overall holistic view.