659640e224
When running multiple concurrent actions, the cleanup phase is run in a separate queue than the main action queue. This can make some commands faster, because less time is spent on bookkeeping in between each file transfer. But as far as I can see, nothing will be sped up much by this yet, because all the existing cleanup actions are very light-weight. This is just groundwork for deferring checksum verification to cleanup time. This change does mean that if the user expects -J2 will mean that they see no more than 2 jobs running at a time, they may be surprised to see 4 in some cases (if the cleanup actions are slow enough to notice). It might also make sense to enable background cleanup without the -J, for at least one cleanup action. Indeed, that's the behavior that -J1 has now. At some point in the future, it make make sense to make the behavior with no -J the same as -J1. The only reason it's not currently is that git-annex can build w/o concurrent-output, and also any bugs in concurrent-output (such as perhaps misbehaving on non-VT100 compatible terminals) are avoided by default by only using it when -J is used.
61 lines
1.6 KiB
Haskell
61 lines
1.6 KiB
Haskell
{- git-annex concurrent state
|
|
-
|
|
- Copyright 2015 Joey Hess <id@joeyh.name>
|
|
-
|
|
- Licensed under the GNU AGPL version 3 or higher.
|
|
-}
|
|
|
|
module Annex.Concurrent where
|
|
|
|
import Annex
|
|
import Annex.Common
|
|
import Annex.Action
|
|
import qualified Annex.Queue
|
|
|
|
import qualified Data.Map as M
|
|
|
|
{- Allows forking off a thread that uses a copy of the current AnnexState
|
|
- to run an Annex action.
|
|
-
|
|
- The returned IO action can be used to start the thread.
|
|
- It returns an Annex action that must be run in the original
|
|
- calling context to merge the forked AnnexState back into the
|
|
- current AnnexState.
|
|
-}
|
|
forkState :: Annex a -> Annex (IO (Annex a))
|
|
forkState a = do
|
|
st <- dupState
|
|
return $ do
|
|
(ret, newst) <- run st a
|
|
return $ do
|
|
mergeState newst
|
|
return ret
|
|
|
|
{- Returns a copy of the current AnnexState that is safe to be
|
|
- used when forking off a thread.
|
|
-
|
|
- After an Annex action is run using this AnnexState, it
|
|
- should be merged back into the current Annex's state,
|
|
- by calling mergeState.
|
|
-}
|
|
dupState :: Annex AnnexState
|
|
dupState = do
|
|
st <- Annex.getState id
|
|
return $ st
|
|
-- each thread has its own repoqueue
|
|
{ Annex.repoqueue = Nothing
|
|
-- avoid sharing eg, open file handles
|
|
, Annex.catfilehandles = M.empty
|
|
, Annex.checkattrhandle = Nothing
|
|
, Annex.checkignorehandle = Nothing
|
|
}
|
|
|
|
{- Merges the passed AnnexState into the current Annex state.
|
|
- Also closes various handles in it. -}
|
|
mergeState :: AnnexState -> Annex ()
|
|
mergeState st = do
|
|
st' <- liftIO $ snd <$> run st stopCoProcesses
|
|
forM_ (M.toList $ Annex.cleanup st') $
|
|
uncurry addCleanup
|
|
Annex.Queue.mergeFrom st'
|
|
changeState $ \s -> s { errcounter = errcounter s + errcounter st' }
|