use 'atomicModifyIORefCAS' where possible #252
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jkachmar
commented
Nov 21, 2025
| readStateVar var = Condition $ do | ||
| touchedVars <- ask | ||
| modifyIORef' touchedVars (Set.insert var.stateVarId) | ||
| liftIO $ atomicModifyIORefCAS_ touchedVars (Set.insert var.stateVarId) |
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these calls are probably only ever sequenced in the course of workflow execution actually, right? so there's no need to be atomic & this should probably stil be modifyIORef'
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Yeah, this is true, workflow execution currently only happens in a single thread.
iand675
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Nov 21, 2025
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jkachmar
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Nov 21, 2025
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| wp <- atomicModifyIORef' w $ \wp -> (throw WorkerAlreadyClosed, wp) | ||
| wp <- liftIO $ atomicModifyIORefCAS w $ \wp -> (throw WorkerAlreadyClosed, wp) |
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hm, atomicModifyIORefCAS is speculative but this is probably fine because only the computation that produces this is retried which is basically just "swap vars"..?
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description
there are a few places where we use
atomicModifyIORefand we already have a transitive dependency onatomic-primops(i'm pretty sure?) and we only support x86_64 & aarch64 architectures so there's no reason not to use the CAS version.