the performance improvement depends on the original implementation, the diffing strategy and the platform you are building the library for. In the old school web world, the usage of the virtual dom improves the performance because reduces the number of searches you have to perform in order to get information about a single node. However, the number of nodes and the time needed to compute them could also be slow, that's why web people are still trying to improve this part of the libraries. They even talk about on thing named "memoized dom" here: https://medium.freecodecamp.org/the-virtual-dom-is-slow-meet-the-memoized-dom-bb19f546cc52