{
  "$type": "site.standard.document",
  "bskyPostRef": {
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    "uri": "at://did:plc:pi6woz4d47bkuws673w2il2r/app.bsky.feed.post/3mnxa3vbeix62"
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  "path": "/t/2026-06-09-informal-ghc-release-status-update-of-a-sort/14250#post_3",
  "publishedAt": "2026-06-10T15:48:42.000Z",
  "site": "https://discourse.haskell.org",
  "tags": [
    "-feager-blackholing"
  ],
  "textContent": "wolverian:\n\n> Somewhat incidentally, I’ve never noticed this recommendation in the GHC documentation before:\n>\n>> We recommend compiling any code that is intended to be run in parallel with the **-feager-blackholing** flag.\n>\n> Huh.\n\nI hadn’t noticed that before either, but I’m guessing it was written in the context of pure code describing a parallel computation with `par`/`pseq`, where you may well be sharing thunks between threads, and eager blackholing might plausibly save work.\n\nMy impression is that explicit concurrency (e.g. with `forkIO` or `async`) is more common these days, and IMHO is easier to think about than parallelism via `par`/`pseq`. And if you’re using explicit concurrency, you’re less likely to be sharing thunks and so the default lazy blackholing is probably better.",
  "title": "2026-06-09: Informal GHC Release Status Update of a Sort"
}