IO::All is one of the most convenient modules I've found in a long time. So I was a little dismayed to come across this little problem.

I have a file which is roughly half a GB (11 million lines), simply doing:

my $line;
while ($line = <>){
  print "$.\n" unless ($. % 10000);  # to keep track of the progress
}
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takes about 7.5 seconds.
With

my $in = FileHandle->new($ARGV[0]);
my $line;
while ($line = $in->getline){
    print "$.\n" unless ($. % 10000);
}
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takes about 23 seconds (same for IO::File); whereas this:

use IO::All;
my $in = io($ARGV[0]);
my $line;
while ($line = $in->getline){
    print "$.\n" unless ($. % 10000);
}
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takes over 10 minutes!

Are others seeing this sort of performance? Is this to be expected?

If it makes any difference, I am running perl 5.8.4 on RedHat Linux 7.3 (reiserfs)