This mod greatly increases game performance for Crushers.
Crushers are extremely heavy on performance in the late game and can cause your FPS to dive dramatically.
The issue is mainly down to the way crusher recipes are implemented and how resources are validated. Resources are validated by checking if they exist in any known recipe. This occurs on all inserters and the crusher itself.
By implementing a cache for known crushable resources we only need to check recipes once, store the resource in the cache, and then check the cache for the resource when needed to validate. This mod does just that.