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 |
|---|---|---|---|---|---|
| 500,000 | 0.24 | 0.24 | 260 | 1874 | 0% 50% 13% 100% |
| 5,000,000 | 2.38 | 2.39 | 1,840 | 1874 | 0% 52% 15% 100% |
| 50,000,000 | 23.68 | 23.69 | 1,840 | 1874 | 0% 0% 0% 100% |
Read the ↓ make, command line, and program output logs to see how this program was run.
Read n-body benchmark to see what this program should do.
notes
llvm version 3.1-2ubuntu1
The Glorious Glasgow Haskell Compilation System, version 7.6.2
n-body Haskell GHC #2 program source code
-- The Computer Language Benchmarks Game -- http://benchmarksgame.alioth.debian.org/ -- -- Contributed by Branimir Maksimovic import Foreign.Ptr import Foreign.Storable import Foreign.Marshal.Alloc import Control.Monad import System.Environment import Text.Printf main = do n <- getArgs >>= readIO.head :: IO Int pPlanets <- fromList planets nbodyInit pPlanets energy pPlanets >>= printf "%.9f\n" run n pPlanets energy pPlanets >>= printf "%.9f\n" run 0 _ = return () run i p = do advance p run (i-1) p data Planet = Planet { x,y,z,vx,vy,vz,mass :: !Double } deriving (Show) offsetMomentum p (px,py,pz) = p { vx = -px / solar_mass, vy = -py / solar_mass, vz = -pz / solar_mass } nbodyInit pPlanets = do let init (px,py,pz) i = do if i < length planets then do p <- peekElemOff pPlanets i init (px + vx p * mass p,py + vy p * mass p, pz + vz p * mass p) (i+1) else return (px,py,pz) s <- init (0,0,0) 0 p <- peek pPlanets poke pPlanets $ offsetMomentum p s squared x y z = x * x + y * y + z * z energy pPlanets = do let energy' e i = if i < length planets then do p <- peekElemOff pPlanets i e1 <- energy'' p (i+1) e e2 <- energy' e (i+1) return $ e + 0.5 * mass p * squared (vx p) (vy p) (vz p)+e1+e2 else return e energy'' p j e = if j < length planets then do pj <- peekElemOff pPlanets j let distance = sqrt $ squared dx dy dz dx = x pj - x p dy = y pj - y p dz = z pj - z p e1 <- energy'' p (j+1) e return $ e - (mass p * mass pj) / distance + e1 else return e energy' 0.0 0 advance pPlanets = do let advance' i = when (i < length planets) $ do let loop j = when (j < length planets) $ do ii <- peekElemOff pPlanets i jj <- peekElemOff pPlanets j let mag = dt / (dSquared * sqrt dSquared) dSquared = squared dx dy dz dx = x ii - x jj dy = y ii - y jj dz = z ii - z jj pokeV pPlanets i ii{ vx = vx ii - dx * mass jj * mag, vy = vy ii - dy * mass jj * mag, vz = vz ii - dz * mass jj * mag } pokeV pPlanets j jj{ vx = vx jj + dx * mass ii * mag, vy = vy jj + dy * mass ii * mag, vz = vz jj + dz * mass ii * mag } loop (j+1) loop (i+1) advance' (i+1) advance'' i = when (i < length planets) $ do p <- peekElemOff pPlanets i pokeC pPlanets i p { x = x p + dt * vx p, y = y p + dt * vy p, z = z p + dt * vz p } advance'' (i+1) advance' 0 advance'' 0 planets = [sun, jupiter, saturn, uranus, neptune] sun = Planet {x = 0, y = 0, z = 0, vx = 0, vy = 0, vz = 0, mass = solar_mass} jupiter = Planet {x = 4.84143144246472090e+00, y = -1.16032004402742839e+00, z= -1.03622044471123109e-01, vx = 1.66007664274403694e-03*dp, vy = 7.69901118419740425e-03*dp, vz = -6.90460016972063023e-05*dp, mass = 9.54791938424326609e-04 * solar_mass} saturn = Planet { x = 8.34336671824457987e+00, y = 4.12479856412430479e+00, z = -4.03523417114321381e-01, vx = -2.76742510726862411e-03*dp, vy = 4.99852801234917238e-03*dp, vz = 2.30417297573763929e-05*dp, mass = 2.85885980666130812e-04 * solar_mass} uranus = Planet {x = 1.28943695621391310e+01,y = -1.51111514016986312e+01,z = -2.23307578892655734e-01, vx = 2.96460137564761618e-03*dp,vy = 2.37847173959480950e-03*dp, vz = -2.96589568540237556e-05*dp, mass = 4.36624404335156298e-05 * solar_mass} neptune = Planet {x = 1.53796971148509165e+01,y = -2.59193146099879641e+01,z = 1.79258772950371181e-01, vx = 2.68067772490389322e-03*dp,vy = 1.62824170038242295e-03*dp, vz = -9.51592254519715870e-05*dp, mass = 5.15138902046611451e-05 * solar_mass} days_per_year = 365.24 solar_mass = 4 * pi ^ 2 dp = days_per_year dt = 0.01 instance Storable Planet where sizeOf _ = 8 * dblSz alignment _ = dblSz peekElemOff p i = peek (plusPtr p (i * sizeOf (undefined::Planet))) pokeElemOff p i e = poke (plusPtr p (i * sizeOf e)) e peek p = do x <- peek (offset 0) y <- peek (offset 1) z <- peek (offset 2) vx <- peek (offset 3) vy <- peek (offset 4) vz <- peek (offset 5) mass <- peek (offset 6) return $ Planet {x=x,y=y,z=z,vx=vx,vy=vy,vz=vz,mass=mass} where offset i = plusPtr (castPtr p::Ptr Double) (i*8) poke p e = do poke (offset 0) $ x e poke (offset 1) $ y e poke (offset 2) $ z e poke (offset 3) $ vx e poke (offset 4) $ vy e poke (offset 5) $ vz e poke (offset 6) $ mass e where offset i = plusPtr (castPtr p::Ptr Double) (i*8) dblSz = sizeOf (undefined::Double) pokeC p i e = do poke (offset 0) $ x e poke (offset 1) $ y e poke (offset 2) $ z e where offset o = (plusPtr (castPtr p::Ptr Double)(o*8+i*64)) pokeV p i e = do poke (offset 3) $ vx e poke (offset 4) $ vy e poke (offset 5) $ vz e where offset o = (plusPtr (castPtr p::Ptr Double)(o*8+i*64)) fromList :: [Planet]->IO (Ptr Planet) fromList l = do let len = length l pa <- mallocBytes (len * sizeOf (undefined::Planet)) let loop [] _ = return () loop (x:xs) i = do poke (pa `plusPtr` (i * sizeOf(undefined::Planet))) x loop xs (i+1) loop l 0 return pa
make, command-line, and program output logs
Mon, 01 Apr 2013 17:44:28 GMT MAKE: mv nbody.ghc-2.ghc nbody.ghc-2.hs /usr/local/src/ghc-7.6.2/bin/ghc --make -fllvm -O2 -XBangPatterns -rtsopts -fexcess-precision nbody.ghc-2.hs -o nbody.ghc-2.ghc_run [1 of 1] Compiling Main ( nbody.ghc-2.hs, nbody.ghc-2.o ) Linking nbody.ghc-2.ghc_run ... rm nbody.ghc-2.hs 2.90s to complete and log all make actions COMMAND LINE: ./nbody.ghc-2.ghc_run 50000000 PROGRAM OUTPUT: -0.169075164 -0.169059907