What do you get with: 
#!/usr/bin/perl

local $/;
open DF,"test.txt";
binmode DF;
my $rec = <DF>;
close DF;

open (DF,'>test1.txt') || die ("Failed to open test1.txt: $!\n");
binmode DF;
print DF $rec;
close DF;

exit;

[download]
?

When I tested on Linux, I found this version ran 4 times faster than yours reading/writing a 10 megabyte file.

In reply to Re: Perl always reads in 4K chunks and writes in 1K chunks... Loads of IO! by snowhare
in thread Perl always reads in 4K chunks and writes in 1K chunks... Loads of IO! by NeilF

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