performance measurements

Each table row shows performance measurements for this Haskell GHC program with a particular command-line input value N.

 N  CPU secs Elapsed secs Memory KB Code B ≈ CPU Load
120.050.06?521  100% 0% 0% 0%
160.730.7367,488521  0% 100% 1% 3%
2024.9825.0271,980521  100% 1% 1% 0%

Read the ↓ make, command line, and program output logs to see how this program was run.

Read binary-trees-redux benchmark to see what this program should do.

 notes

The Glorious Glasgow Haskell Compilation System, version 7.8.2

 binary-trees-redux Haskell GHC program source code

--
-- The Computer Language Benchmarks Game
-- http://benchmarksgame.alioth.debian.org/
--
-- Contributed by Don Stewart
--

import System.Environment
import Data.Bits
import Text.Printf

--
-- an artificially strict tree. 
--
-- normally you would ensure the branches are lazy, but this benchmark
-- requires strict allocation.
--
data Tree = Nil | Node !Int !Tree !Tree

minN = 4

io s n t = printf "%s of depth %d\t check: %d\n" s n t

main = do
    n <- getArgs >>= readIO . head
    let maxN     = max (minN + 2) n
        stretchN = maxN + 1

    -- stretch memory tree
    let c = check (make 0 stretchN)
    io "stretch tree" stretchN c

    -- allocate a long lived tree
    let !long    = make 0 maxN

    -- allocate, walk, and deallocate many bottom-up binary trees
    let vs = depth minN maxN
    mapM_ (\((m,d,i)) -> io (show m ++ "\t trees") d i) vs

    -- confirm the the long-lived binary tree still exists
    io "long lived tree" maxN (check long)

-- generate many trees
depth :: Int -> Int -> [(Int,Int,Int)]
depth d m
    | d <= m    = (2*n,d,sumT d n 0) : depth (d+2) m
    | otherwise = []
  where n = 1 `shiftL` (m - d + minN)

-- allocate and check lots of trees
sumT :: Int -> Int -> Int -> Int
sumT d 0 t = t
sumT  d i t = sumT d (i-1) (t + a + b)
  where a = check (make i    d)
        b = check (make (-i) d)

-- traverse the tree, counting up the nodes
check :: Tree -> Int
check Nil          = 0
check (Node i l r) = i + check l - check r

-- build a tree
make :: Int -> Int -> Tree
make i 0 = Node i Nil Nil
make i d = Node i (make (i2-1) d2) (make i2 d2)
  where i2 = 2*i; d2 = d-1

 make, command-line, and program output logs

Wed, 16 Apr 2014 23:19:48 GMT

MAKE:
mv binarytreesredux.ghc binarytreesredux.hs
/usr/local/src/ghc-7.8.2/bin/ghc --make -fllvm -O2 -XBangPatterns -threaded -rtsopts -funbox-strict-fields binarytreesredux.hs -o binarytreesredux.ghc_run
[1 of 1] Compiling Main             ( binarytreesredux.hs, binarytreesredux.o )
Linking binarytreesredux.ghc_run ...
rm binarytreesredux.hs
1.35s to complete and log all make actions

COMMAND LINE:
./binarytreesredux.ghc_run +RTS -H64M -M64M -RTS 20

PROGRAM OUTPUT:
stretch tree of depth 21	 check: -1
2097152	 trees of depth 4	 check: -2097152
524288	 trees of depth 6	 check: -524288
131072	 trees of depth 8	 check: -131072
32768	 trees of depth 10	 check: -32768
8192	 trees of depth 12	 check: -8192
2048	 trees of depth 14	 check: -2048
512	 trees of depth 16	 check: -512
128	 trees of depth 18	 check: -128
32	 trees of depth 20	 check: -32
long lived tree of depth 20	 check: -1

Revised BSD license

  Home   Conclusions   License   Play