u/kosmikusin r/haskell • Recommends
The Haskell Unfolder Episode 36: concurrency and the FFI
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The Haskell Unfolder Episode 36: concurrency and the FFI
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3.4K subscribers • 14 videos on Hallway
- Recommended by 2 people: 1 on Lobsters and 1 in engineering communities.
Intermediate. Assumes working knowledge.
1.5K views1 year ago2 recommendations
Programming languagesSystems programmingHaskellConcurrency and parallelismPerformance and optimization
An explanation of safe versus unsafe foreign function imports in Haskell and how they interact with GHC's runtime and concurrency.
There are two primary ways to import C functions in Haskell: "unsafe" and "safe". We will first briefly recap what this means: `unsafe` functions are fast but cannot call back into Haskell, `safe` functions are much slower but can. As we will see in this episode, however, there are many more differences between `unsafe` and `safe` functions, especially in a concurrent setting. In particular, `safe` functions are not always safer!Why it's here
2 people recommend thisWhat people say. Recommended for its clear explanation of Haskell's FFI behavior under concurrent workloads.
Hecateon Lobsters • Recommends
The Haskell Unfolder Episode 36: concurrency and the FFI
u/massudawin r/haskell • Mentions
On “Question regarding GHC green threads”
Depends if those are ffi calls or just using blocking io via io manager. Also there is no way to limit number number of green threads, there will be as many as you call forkIO.
This might be useful in understanding: link to this video
u/TechnoEmpressin r/haskell • Mentions
On “Should FFI always be IO?”
Side-idea but you could absolutely use a finer-grained effect system (like effectful) to create an `FFI` effect that corresponds semantically to your definition of "I do outside calls and they are / are not safely retryable and are / are not interruptible" (watch link to this video for more interesting details)