foreach (@mergedlogs)
{
  open FH, ">>mergedlogs.txt" or die "can't open mergedlogs.txt: $!";
  print FH "$_\n";
  close FH
}

[download]

You are opening and closing the file on every single record. Don't do that. Instead:

open FH, ">>mergedlogs.txt" or die "can't open mergedlogs.txt: $!";
$| = 0; # just in case
foreach (@mergedlogs)
{
  print FH "$_\n";
}
close FH;

[download]

There are other ways this could be improved, but this should get you a large gain for little effort.

In reply to Re: Write large array to file, very slow by hippo
in thread Write large array to file, very slow by junebob

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