GHC's Runtime System - Ben Gamari - 2023 GHC Contributor's Workshop

An overview of the runtime system that powers compiled Haskell code, including the relationship of the RTS to the rest of the system, the structure of the heap, memory management, concurrency, the bytecode interpreter, and how to debug it when things go wrong. This talk is useful for any Haskell developer who wants to achieve greater insight into the run-time performance of Haskell code, in addition to those who want to work on GHC itself. This talk was presented at the 2023 GHC Contributor's Workshop in Rapperswil, Switzerland, colocated with Zurihac. The workshop was arranged by the Haskell Foundation, OST Eastern Switzerland University of Applied Sciences, and the GHC development team. Ben has been contributing to GHC for over a decade and been working as a full-time compiler engineer at Well-Typed since 2015. In that time he has worked across the compiler, from parsing to code generation to release management and development infrastructure. His contributions include GHC’s non-moving concurrent garbage collector, GHC’s type-reflection implementation, and numerous improvements in profiling. He tends to find himself working near the back end of GHC’s compilation pipeline and runtime system.