Lightning Talk: Fiber Scheduler vs. General-Purpose Parallel Client
Hayao Kimura • Matsuyama, Ehime, Japan • Japanese • Lightning Talk

Date: April 17, 2025
Published: May 27, 2025
Announced: unknown

In an effort to build a general-purpose parallel request client in Ruby—something anyone in our team could easily use—I ran into an unexpected roadblock: the limitations of the Fiber Scheduler. This talk walks through the journey from parallelizing Faraday requests, to exploring Fiber Scheduler as a lightweight alternative to threads, and ultimately hitting a wall when trying to support gRPC and AWS SDK. I'll explain why Fiber Scheduler couldn't handle gRPC due to its C-level implementation, and how that led to a shift toward using threads instead. If you're curious about the real-world limitations of Ruby's Fiber Scheduler and what it takes to design a truly flexible parallel request client, this talk is for you.

RubyKaigi 2025