Re[2]: [Haskell-cafe] ansi2html - one program, several issues
Hello Krzysztof, Sunday, July 20, 2008, 12:49:54 AM, you wrote: on the 32-bit computers 36x memreqs for storing large strings in memory is a rule, on 64-bit ones - 72x > I forgot to mention that the memory consumption is several times > higher than file size. On 8,3 Mb file: >> 532 MB total memory in use (4 MB lost due to fragmentation). > Having that 8 Mb in memory is not the problem. 532 Mb is another > story. In general, the program consumes roughly 64 times more memory > than file size and it scales linearly. > > Best regards > Christopher Skrzetnicki > On Sat, Jul 19, 2008 at 9:52 PM, Chaddai Fouche <[EMAIL PROTECTED]> wrote: > 2008/7/19 Krzysztof Skrzetnicki < [EMAIL PROTECTED]>: >> Hi all > >> >> 1) Profiling shows that very simple functions are source of great memory and >> time consumption. However, if I turn them off and simply print their input >> arguments instead, the overall time and memory consumption doesn't change. >> But now another function is acting badly. My guess: somehow the cost of >> Parsec code is shifted into whatever function is using it's output. Let's >> see: > > > Are you using Parsec to parse the whole file ? Then your problem is > there : Parsec needs to read and process the whole file before it can > give us any output since it thinks it could have to give us an error > instead and it can't be sure of that before he has read the whole > thing... > In your case, your problem is such that you would prefer to treat the > file as a stream, isn't it ? > There are some parser library that can give output lazily (look at > polyparse flavour), another option would be to only use Parsec where > you need it and just read and print the ordinary text for example. > -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re[2]: [Haskell-cafe] ansi2html - one program, several issues
Hello Krzysztof, Sunday, July 20, 2008, 1:55:45 AM, you wrote: >>> 532 MB total memory in use (4 MB lost due to fragmentation). i think that Parsec library should hold entire file in memory only when you use 'try' for whole file. otherwise it should omit data as proceeded -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Re[2]: [Haskell-cafe] ansi2html - one program, several issues
On Sun, Jul 20, 2008 at 12:34 AM, Bulat Ziganshin <[EMAIL PROTECTED]> wrote: > Hello Krzysztof, > > Sunday, July 20, 2008, 1:55:45 AM, you wrote: > >>> 532 MB total memory in use (4 MB lost due to fragmentation). > > i think that Parsec library should hold entire file in memory only when > you use 'try' for whole file. otherwise it should omit data as > proceeded > > That's exactly what I thought. But even if I remove the only 'try' I use the memory consumption remains unchanged: C:\cygwin\home\Metharius\killer\KillerPy\ansi2html\ansi2html_old.exe duzy.log +RTS -sstderr File duzy.log processed. It took 5.046875s. File size was 4166578 characters. 3,950,649,704 bytes allocated in the heap 535,544,056 bytes copied during GC 117,603,408 bytes maximum residency (9 sample(s)) 1,647,828 bytes maximum slop 265 MB total memory in use (2 MB lost due to fragmentation) Generation 0: 7527 collections, 0 parallel, 0.86s, 0.86s elapsed Generation 1: 9 collections, 0 parallel, 0.80s, 0.81s elapsed INIT time0.02s ( 0.00s elapsed) MUT time3.20s ( 3.63s elapsed) GCtime1.66s ( 1.67s elapsed) EXIT time0.00s ( 0.00s elapsed) Total time4.88s ( 5.30s elapsed) %GC time 34.0% (31.6% elapsed) Alloc rate1,227,386,315 bytes per MUT second Productivity 65.7% of total user, 60.5% of total elapsed One more thing to note: with partial parsing there is no longer a difference between mapM_ and mapMPar. Best regards Christopher Skrzętnicki ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Re[2]: [Haskell-cafe] ansi2html - one program, several issues
2008/7/20 Krzysztof Skrzętnicki <[EMAIL PROTECTED]>: > On Sun, Jul 20, 2008 at 12:34 AM, Bulat Ziganshin > <[EMAIL PROTECTED]> wrote: >> >> Hello Krzysztof, >> >> Sunday, July 20, 2008, 1:55:45 AM, you wrote: >> >>> 532 MB total memory in use (4 MB lost due to fragmentation). >> >> i think that Parsec library should hold entire file in memory only when >> you use 'try' for whole file. otherwise it should omit data as >> proceeded >> > > That's exactly what I thought. But even if I remove the only 'try' I use the > memory consumption remains unchanged: It's true, but in your case your output is almost the raw input data, which means that even without a noxious "try", you still have the whole file in memory. Well hopefully not with your latest code, which I would really like to see. -- Jedaï ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Re[2]: [Haskell-cafe] ansi2html - one program, several issues
On Sun, Jul 20, 2008 at 7:25 AM, Chaddaï Fouché <[EMAIL PROTECTED]> wrote: > > > That's exactly what I thought. But even if I remove the only 'try' I use > the > > memory consumption remains unchanged: > > It's true, but in your case your output is almost the raw input data, > which means that even without a noxious "try", you still have the > whole file in memory. Well hopefully not with your latest code, which > I would really like to see. Here is the part that actually changed: --- split c str = let (p,ps) = aux str in (p:ps) where aux [] = ([],[]) aux (x:cs) = let (xs,xss) = aux cs in if x == c then ([c],(xs:xss)) else ((x:xs),xss) splitPred :: (Eq a) => (a -> Bool) -> [a] -> [[a]] splitPred pr str = let (p,ps) = aux str in (p:ps) where aux [] = ([],[]) aux (x:cs) = let (xs,xss) = aux cs in if pr x then ([],((x:xs):xss)) else ((x:xs),xss) doOneFile :: String -> IO () doOneFile fname = do t1 <- getCurrentTime doesFileExist (fname ++ ".html") >>= \b -> if b then hPutStrLn stderr $ printf "File already processed, skipping: %s" fname else do src <- readFile fname out <- openFile (fname ++ ".html") WriteMode hSetBuffering out (BlockBuffering (Just 64000)) hPutStrLn out "" hPutStrLn out "" hPutStrLn out "" hPutStrLn out "" let extractData = \p -> case p of Right x -> x Left err -> (trace . show $ err) [] let srcSplit = splitPred (`elem`"\n") src let parsed = concatMap (extractData . parse mainParser fname) srcSplit execStateT (hPrintHtml (St id)) (out,emptyStyle) -- wypisujemy pierwszy wiersz execStateT (mapM_ hPrintHtml parsed) (out,emptyStyle) hPutStrLn out "" hPutStrLn out "" hPutStrLn out "" t2 <- getCurrentTime hPutStrLn stderr $ printf "File %s processed. It took %s. File size was %d characters." fname (show $ diffUTCTime t2 t1) (length src) hClose out -- The whole file is also attached. You will find there another (worse) implementation of split and a little bit of code similar to thread pool stuff. On Sun, Jul 20, 2008 at 8:17 AM, John Meacham <[EMAIL PROTECTED]> wrote: > On Sun, Jul 20, 2008 at 02:34:09AM +0400, Bulat Ziganshin wrote: > > i think that Parsec library should hold entire file in memory only when > > you use 'try' for whole file. otherwise it should omit data as > > proceeded > > I do not believe that is the case, since the return type of runParser > "Either ParseError a" means that before you can extract the result of > the parse from the 'Right' branch, it must evaluate whether the result > is 'Left' or 'Right' meaning it needs to parse the whole input in order > to determine whether the parse was succesful. > It's true it has to parse the whole file, but it is not true it has to reside in the memory: only the results must be there. In this case, when the result is 1-1 transformation of input, it is true. But consider this program: module Main where import Text.ParserCombinators.Parsec par = eof <|> (char 'a' >> par) alst = take 2 (repeat 'a') main = print (runParser par () "" alst) It runs in constant memory: $ ./partest.exe +RTS -sstderr C:\cygwin\home\Metharius\killer\killerPy\ansi2html\partest.exe +RTS -sstderr Right () 84,326,845,636 bytes allocated in the heap 22,428,536 bytes copied during GC 9,684 bytes maximum residency (1 sample(s)) 13,848 bytes maximum slop 1 MB total memory in use (0 MB lost due to fragmentation) Generation 0: 160845 collections, 0 parallel, 0.63s, 0.63s elapsed Generation 1: 1 collections, 0 parallel, 0.00s, 0.00s elapsed INIT time0.02s ( 0.00s elapsed) MUT time 54.31s ( 54.55s elapsed) GCtime0.63s ( 0.63s elapsed) EXIT time0.00s ( 0.00s elapsed) Total time 54.95s ( 55.17s elapsed) %GC time 1.1% (1.1% elapsed) Alloc rate1,552,176,623 bytes per MUT second Productivity 98.8% of total user, 98.4% of total elapsed Best regards Christopher Skrzętnicki ansi2html.hs Description: Binary data ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Re[2]: [Haskell-cafe] ansi2html - one program, several issues
I played with another approach without any parser library, just with plain pattern matching. The idea was to create function to match all different cases of codes. Since I already got most of the code, it was quite easy to do. The core function consist of cases like those: > parse ('\ESC':'[':'1':';':'4':'0':'m':rest) = modifyAndPrint (\x -> x { bgcol = light black })>> parse rest > parse ('\ESC':'[':'1':';':'4':'1':'m':rest) = modifyAndPrint (\x -> x { bgcol = light red })>> parse rest > parse ('\ESC':'[':'1':';':'4':'2':'m':rest) = modifyAndPrint (\x -> x { bgcol = light green })>> parse rest > parse ('\ESC':'[':'1':';':'4':'3':'m':rest) = modifyAndPrint (\x -> x { bgcol = light yellow })>> parse rest If you have read the old code you should recognize some parts of it here. It should consume rather constant amount of memory. To my surprise it consumed almost exactly the same amount of memory as the previous program. Turns out the problematic line was this: >hPutStrLn stderr $ printf "File %s processed. It took %s. File size was %d characters." fname (show $ diffUTCTime t2 t1) *(length src)* It computed length of the input file. Needless to say, because "src" was actually the input file parsed previously, it was all hanging in the memory. Having removed that reference to src both programs (the one that parses input per line and the most recent one) are running in constant memory (2Mb). This doesn't apply to the first program, which has to read whole file before producing any output. And the last note: the new program is also 2x faster, perhaps due to very simple structure that is easy to optimize. It also makes sense now to use mapMPar as it reduces run time by 30%. The full code is in attachments. Best regards Christopher Skrzętnicki ansi2html.hs Description: Binary data ansi2html.hs Description: Binary data ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe