Re: [Haskell-cafe] zip-archive performance/memmory usage
I was interested to see if I could determine what was happening with this. After some playing around, I noticed the code was running significantly faster if I *didn't* compile it, but ran it with 'runghc' instead (running under ghci was also fast). Here are the running times I found. The 'Zip.hs' program comes with the zip-archive package. The runtime of the compiled version didn't seem to be affected by optimisations. Regardless, I'm quite surprised running interpreted was significantly faster than compiled. time runghc ./Zip.hs -l ~/jdk1.6.0_05-src.zip 1.48s user 0.17s system 97% cpu 1.680 total time ./dist/build/Zip/Zip -l ~/jdk1.6.0_05-src.zip 89.00s user 1.06s system 98% cpu 1:31.84 total The file 'jdk1.6.0_05-src.zip' was just an 18MB zip file I had lying around. I'm using ghc 6.12.1 Cheers, -- David Powell On Tue, Aug 10, 2010 at 12:10 PM, Jason Dagit da...@codersbase.com wrote: On Mon, Aug 9, 2010 at 4:29 PM, Pieter Laeremans pie...@laeremans.orgwrote: Hello, I'm trying some haskell scripting. I'm writing a script to print some information from a zip archive. The zip-archive library does look nice but the performance of zip-archive/lazy bytestring doesn't seem to scale. Executing : eRelativePath $ head $ zEntries archive on an archive of around 12 MB with around 20 files yields Stack space overflow: current size 8388608 bytes. So it's a stack overflow at about 8 megs. I don't have a strong sense of what is normal, but that seems like a small stack to me. Oh, actually I just check and that is the default stack size :) I looked at Zip.hs (included as an example). The closest I see to your example is some code for listing the files in the archive. Perhaps you should try the supplied program on your archive and see if it too has a stack overflow. The line the author uses to list files is: List- mapM_ putStrLn $ filesInArchive archive But, you're taking the head of the entries, so I don't see how you'd be holding on to too much data. I just don't see anything wrong with your program. Did you remember to compile with optimizations? Perhaps try the author's way of listing entries and see if performance changes? The script in question can be found at : http://github.com/plaeremans/HaskellSnipplets/blob/master/ZipList.hs I'm using the latest version of haskell platform. Are these libaries not production ready, or am I doing something terribly wrong ? Not production ready would be my assumption. I think an iteratee style might be more appropriate for these sorts of nested streams of potentially large size anyway. I'm skeptical of anything that depends on lazy bytestrings or lazy io. In this case, the performance would appear to be depend on lazy bytestrings. You might want to experiment with increasing the stack size. Something like this: ./ZipList +RTS -K100M -RTS foo.zip Jason ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] zip-archive performance/memmory usage
On 10/08/10 00:29, Pieter Laeremans wrote: Hello, I'm trying some haskell scripting. I'm writing a script to print some information from a zip archive. The zip-archive library does look nice but the performance of zip-archive/lazy bytestring doesn't seem to scale. Executing : eRelativePath $ head $ zEntries archive on an archive of around 12 MB with around 20 files yields Stack space overflow: current size 8388608 bytes. The script in question can be found at : http://github.com/plaeremans/HaskellSnipplets/blob/master/ZipList.hs I'm using the latest version of haskell platform. Are these libaries not production ready, or am I doing something terribly wrong ? I downloaded your program and compiled it (GHC 6.12.1, zip-archive 0.1.1.6, bytestring 0.9.1.5). I ran it on the JVM src.zip (20MB, ~8000 files) and it sat there for a minute (67s), taking 2.2% memory according to top, then completed successfully. Same behaviour with -O2. Which compares very badly in time to the instant return when I ran unzip -l on the same file, but I didn't see any memory problems. Presumably your archive is valid and works with unzip and other tools? Thanks, Neil. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] zip-archive performance/memmory usage
Hello, I'm trying some haskell scripting. I'm writing a script to print some information from a zip archive. The zip-archive library does look nice but the performance of zip-archive/lazy bytestring doesn't seem to scale. Executing : eRelativePath $ head $ zEntries archive on an archive of around 12 MB with around 20 files yields Stack space overflow: current size 8388608 bytes. The script in question can be found at : http://github.com/plaeremans/HaskellSnipplets/blob/master/ZipList.hs I'm using the latest version of haskell platform. Are these libaries not production ready, or am I doing something terribly wrong ? kind regards, Pieter -- Pieter Laeremans pie...@laeremans.org The future is here. It's just not evenly distributed yet. W. Gibson ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] zip-archive performance/memmory usage
On 10 August 2010 09:29, Pieter Laeremans pie...@laeremans.org wrote: Hello, I'm trying some haskell scripting. I'm writing a script to print some information from a zip archive. The zip-archive library does look nice but the performance of zip-archive/lazy bytestring doesn't seem to scale. Executing : eRelativePath $ head $ zEntries archive on an archive of around 12 MB with around 20 files yields Stack space overflow: current size 8388608 bytes. The script in question can be found at : http://github.com/plaeremans/HaskellSnipplets/blob/master/ZipList.hs I'm using the latest version of haskell platform. Are these libaries not production ready, or am I doing something terribly wrong ? I'm not familiar with the library, but I have a sneaking suspicion that you're doing something terribly wrong, namely keeping the entire archive in memory rather than using it lazily. -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
