cf: https://github.com/fumieval/sandbox/blob/3f4cc089f6321c9e5c43b7a63f8662fd665fa6a1/benchmarks/mutable.hs

mutvar.hs

import Gauge.Main
import Control.Monad
import Control.Monad.State.Strict
import Data.IORef
import qualified Data.Vector.Unboxed.Mutable as V
import Data.Primitive.MutVar

{-
benchmarked IORef
time                 3.196 μs   (3.170 μs .. 3.226 μs)
                     0.996 R²   (0.989 R² .. 1.000 R²)
mean                 3.230 μs   (3.205 μs .. 3.293 μs)
std dev              120.7 ns   (54.65 ns .. 225.7 ns)
variance introduced by outliers: 20% (moderately inflated)

benchmarked vector
time                 1.374 μs   (1.370 μs .. 1.377 μs)
                     1.000 R²   (1.000 R² .. 1.000 R²)
mean                 1.372 μs   (1.370 μs .. 1.374 μs)
std dev              6.750 ns   (5.682 ns .. 8.349 ns)

benchmarked mutvar
time                 3.212 μs   (3.194 μs .. 3.235 μs)
                     0.999 R²   (0.998 R² .. 1.000 R²)
mean                 3.211 μs   (3.201 μs .. 3.226 μs)
std dev              41.10 ns   (27.42 ns .. 66.97 ns)

benchmarked state
time                 1.776 ns   (1.771 ns .. 1.781 ns)
                     1.000 R²   (1.000 R² .. 1.000 R²)
mean                 1.777 ns   (1.774 ns .. 1.780 ns)
std dev              11.01 ps   (9.129 ps .. 13.57 ps)
-}

main = do
  ref  <- newIORef (0 :: Int)
  vec  <- V.replicate 1 (0 :: Int)
  mvar <- newMutVar (0 :: Int)
  defaultMain
    [ bench "IORef" $ nfIO $ replicateM_ 1000 $ modifyIORef' ref (+ 1)
    , bench "vector" $ nfIO $ replicateM_ 1000 $ V.modify vec (+ 1) 0
    , bench "mutvar" $ nfIO $ replicateM_ 1000 $ modifyMutVar' mvar (+ 1)
    , bench "state"
    $ nfIO
    $ return
    $ flip execState (0 :: Int)
    $ replicateM_ 1000
    $ modify' (+ 1)
    ]