But this could eat a lot of memory, as the files are huge. So I found Tie::File online, that happens not to load arrays in memory. 1st question, is that correct ?

Hi ansh007

Apparently Tie::File doesn't fast big files well it slow :D Don't use Tie::File its a toy :)

• I hate to be there bearer of bad tidings here, but if you'd ever tried using Tie::File on a 34GB file, you'd never be suggesting it to others. It would take weeks to complete.
• Oh, this is sad. I just had the script work on a 1G+ file, and extrapolated the time to about 17hrs of processing for a 34G file.
• Using Tie::File on such a huge file -- or any file over a few (single digit) megabytes is stupid. It will use huge amounts of cpu and be very slow.
• a file size that is too large to use with Tie::File? 1000 lines/100kB
• Please do not suggest the use of Tie::File for use with files bigger than a few tens of megabytes. Using it makes processing such files 10s or 100s of times slower than using normal line-by-line access for no benefit.
• Please try this yourself--say read the middle line in a 1 or 2GB file--before suggesting it to others.
• Tie::File is slow, to write a 1mb file 137.506 seconds, versus 0.197 seconds without it
• Tie::File: Speed and memory issue with large files

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