GHC.Event.Thread.eventManager has a lot of indirections
Current eventManager
:
eventManager :: IORef (IOArray Int (Maybe (ThreadId, EventManager)))
eventManager = unsafePerformIO $ do
...
That's a lot of indirections just to grab your thread's event manager.
Consider the following, which I believe would improve the performance of this:
data UnliftedIORef :: TYPE 'UnliftedRep -> Type where
UnliftedIORef :: MutVar# RealWorld a -> UnliftedIORef a
eventManager :: UnliftedIORef (MutableArray# RealWorld Things)
data Things = Things !ThreadId !EventManager
I think the Maybe can be eliminated. I'm unsure. What makes me think it can be is the following snippet:
getSystemEventManager :: IO (Maybe EventManager)
getSystemEventManager = do
t <- myThreadId
(cap, _) <- threadCapability t
eventManagerArray <- readIORef eventManager
mmgr <- readIOArray eventManagerArray cap
return $ fmap snd mmgr
getSystemEventManager_ :: IO EventManager
getSystemEventManager_ = do
Just mgr <- getSystemEventManager
return mgr
{-# INLINE getSystemEventManager_ #-}
Trac metadata
Trac field | Value |
---|---|
Version | 8.6.2 |
Type | FeatureRequest |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | libraries/base |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |