$dbh->do(qq{ALTER TABLE $table DISABLE KEYS});

my $base_query = qq{INSERT INTO $table VALUES };
my $query      = $base_query;
my $count      = 0;
my $max_rows   = 10000; # adjust it to your needs

while ($line = <FILE>)
{
    my @values = something_from($line);

    $query .= "," if $count++;
    $query .= "(" 
           . join(",", map { $dbh->quote($_) } @values )    
           . ")";
    if ($count > $max_rows)
    {
        $dbh->do($query) 
            or die "something wrong ($DBI::errstr)";
        $query = $base_query;
        $count = 0;
    }
}

$dbh->do($query) if $count;

$dbh->do(qq{ALTER TABLE $table ENABLE KEYS});