Execution domains in GHC/Haskell (Lightning Talk)

on YouTube ↗14m

" summary

Proposes adding domains to GHC: per-domain local heaps with independent GC and schedulers plus explicit shared global heap regions to avoid duplicating hundreds of gigabytes across processes. Shows a concrete API sketch—fork-like spawn using static pointers, message passing over channels with messages as compact normal forms—and a simple implementation path borrowing OCaml/Erlang ideas. Calls out tricky cases: CAF handling and the immutability requirement on global-shared data and how occasional updates might be represented.

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" chapters (6)

1. 0:00Execution domains in GHC
2. 1:46Scaling GHC runtime challenges
3. 4:55Shared runtime bottleneck
4. 7:26Proposal for execution domains
5. 9:55Benefits and implementation path
6. 10:39Q&A

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