ABSTRACT
Some code bottlenecks (parts of the code base that slow the application) might not be caught by simple profiling tools: sometime a slow application can be explained by caveats in the way the application is designed.
This chapter will present three main sources of design patterns that might be slowing your application: uncontrolled reactivity, where too much happens (also known as “reactivity hell”), making R perform too much computation, and data source management.
