If you mean controlling the size of the data in the array, you can do something like:

my @arrays = ( [] );
my $length = 0;
while (<>) {
   if (length $_ + $length >= 24 * 1024) {
       push @arrays,[$_];
       $length = length $_;
   }
   else {
       push @{$arrays[-1]},$_;
       $length += length $_;
   }
}
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which will fill @arrays with anonymous arrays smaller than 24 Kbytes worth of data (Except when the lines are bigger than 24 Kbytes by themselves) .

Controlling the actual size of the arrays (in terms of allocated memory) is quite a lot trickier (if at all possible) in pure perl.

Another question would of course be: why would you want this anyway?

-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.
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