Оптимизация памяти в Haskell, конвейеры, аттопарсек и контейнеры

Я пытаюсь еще больше оптимизировать парсер и хранилище pipe-attoparsec, но у меня возникают проблемы с уменьшением использования памяти.

Данный аккаунт-parser.hs

{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE NoImplicitPrelude #-}

import Protolude hiding (for)

import Data.Hashable
import Data.IntMap.Strict (IntMap)
import Data.Vector (Vector)
import Pipes
import Pipes.Parse
import Pipes.Safe (MonadSafe, runSafeT)
import qualified Data.Attoparsec.ByteString.Char8 as AB
import qualified Data.IntMap.Strict as IM
import qualified Data.Vector as Vector
import qualified Pipes.Attoparsec as PA
import qualified Pipes.ByteString as PB
import qualified Pipes.Safe.Prelude as PSP

-- accountid|account-name|contractid|code

data AccountLine = AccountLine {
    _accountId         :: !ByteString,
    _accountName       :: !ByteString,
    _accountContractId :: !ByteString,
    _accountCode       :: !Word32
    } deriving (Show)

type MapCodetoAccountIdIdx = IntMap Int

data Accounts = Accounts {
    _accountIds   :: !(Vector ByteString),
    _cache        :: !(IntMap Int),
    _accountCodes :: !MapCodetoAccountIdIdx
    } deriving (Show)


parseAccountLine :: AB.Parser AccountLine
parseAccountLine = AccountLine <$>
    getSubfield <* delim <*>
    getSubfield <* delim <*>
    getSubfield <* delim <*>
    AB.decimal <* AB.endOfLine
    where getSubfield = AB.takeTill (== '|')
          delim = AB.char '|'

--

aempty :: Accounts
aempty = Accounts Vector.empty IM.empty IM.empty

aappend :: Accounts -> AccountLine -> Accounts
aappend (Accounts ids a2i cps) (AccountLine aid an cid cp) =
    case IM.lookup (hash aid) a2i of
        Nothing -> Accounts
                (Vector.snoc ids (toS aid))
                (IM.insert (hash aid) (length ids) a2i)
                (IM.insert (fromIntegral cp) (length ids) cps)
        Just idx -> Accounts ids a2i (IM.insert (fromIntegral cp) idx cps)

foldAccounts :: (Monad m) => Parser AccountLine m Accounts
foldAccounts = foldAll aappend aempty identity

readByteStringFile :: (MonadSafe m) => FilePath -> Producer' ByteString m ()
readByteStringFile file = PSP.withFile file ReadMode PB.fromHandle

accountLines :: Text -> MonadSafe m => Producer AccountLine m (Either (PA.ParsingError, Producer ByteString m ()) ())
accountLines filename = PA.parsed parseAccountLine (readByteStringFile (toS filename))


main :: IO ()
main = do
    [filename] <- getArgs
    x <- runSafeT $ runEffect $ Pipes.Parse.evalStateT foldAccounts (accountLines (toS filename))

    print $ sizes x

sizes :: Accounts -> (Int, Int, Int)
sizes (Accounts aid xxx acp) = (Vector.length aid, IM.size xxx, IM.size acp)

Скомпилировано с помощью GHC 8.0.2 (stack ghc -- -O2 -rtsopts -threaded -Wall account-parser.hs)

Я не могу уменьшить использование памяти. Мне нужно быстро искать, поэтому IntMaps. Размер файла составляет около 20 МБ (и неэффективен). Большая часть данных должна уместиться в 5 МБ.

$ ./account-parser /tmp/accounts +RTS -s
(5837,5837,373998)
   1,631,040,680 bytes allocated in the heap
     221,765,464 bytes copied during GC
      41,709,048 bytes maximum residency (13 sample(s))
       2,512,560 bytes maximum slop
              82 MB total memory in use (0 MB lost due to fragmentation)

                                     Tot time (elapsed)  Avg pause  Max pause
  Gen  0      2754 colls,     0 par    0.105s   0.142s     0.0001s    0.0002s
  Gen  1        13 colls,     0 par    0.066s   0.074s     0.0057s    0.0216s

  TASKS: 4 (1 bound, 3 peak workers (3 total), using -N1)

  SPARKS: 0 (0 converted, 0 overflowed, 0 dud, 0 GC'd, 0 fizzled)

  INIT    time    0.000s  (  0.001s elapsed)
  MUT     time    0.324s  (  0.298s elapsed)
  GC      time    0.171s  (  0.216s elapsed)
  EXIT    time    0.000s  (  0.005s elapsed)
  Total   time    0.495s  (  0.520s elapsed)

  Alloc rate    5,026,660,297 bytes per MUT second

  Productivity  65.5% of total user, 58.4% of total elapsed

gc_alloc_block_sync: 0
whitehole_spin: 0
gen[0].sync: 0
gen[1].sync: 0

И профиль: