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How can I process large files efficiently?

( #10432=categorized question: print w/ replies, xml ) Need Help??
Contributed by Anonymous Monk on May 06, 2000 at 01:08 UTC
Q&A  > files


Description:

I'm searching large (500meg) log files. My CGI script usually takes 3-4 min. to search text. Are there any tricks (like dividing the logfile, etc.) that could make it more efficient?

Answer: How can I process large files efficiently?
contributed by devslashneil

You could use Tie::File to bind an array to a file, and then perform searches on the array without loading the file into memory.

"The file is not loaded into memory, so this will work even for gigantic files."

Hope this helps

- Neil

Answer: How can I process large files efficiently?
contributed by btrott

Here are some tips:

  • Are you loading the entire file into a variable or processing it line by line? Process it line by line for faster results, because you won't be thrashing memory.
  • Are you using regular expressions where you're searching for a variable? Make sure you're using the /o modifier if the variable is the same each time through the loop.

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