Authentication problem

[Levi E. Stanley]

Hi,
Been seeing problems with an Authenticate script lately.  It was working 
fine up to the time I started getting slammed with traffic.  I don't see 
any connection problems in the log file at all.  But what I have noticed 
on the site is, I will click to go to download a file from the secure 
area, and it won't prompt me for a username and password until minutes 
later, like it is being delayed or something.  Is this normal behavior 
from high traffic? 

More Info:
The server isn't even being over worked, it has 4 cpus and on high 
traffic hours, it is around 2 on cpu load.  So it can only be two 
possibilities, the script or apache configuration.  The apache version I 
am using http-2.0.53, and mod_perl-2.0.0-RC4.

Here is the code:
package My::Authenticate;
use strict;
use ModPerl::Util ();
use Apache::Const qw(OK DECLINED AUTH_REQUIRED);
use Apache::Log;
use DBI;
sub handler{
       my $r = shift;
       my $s = Apache->server;
       return Apache::DECLINED unless $r->is_initial_req;
       my ($status,$password) = $r->get_basic_auth_pw;
       my $username = $r->user;
       return $status unless $status == Apache::OK;
       my $hostname = $r->hostname;
       $hostname=~/(.*?\.)?(.*?)\.[a-z]{3}$/;
       my $table_access = $2."_access";
       my $dbh = 
DBI->connect('DBI:mysql:database=site_authentication;host=xxx.xxx.xxx.xxx','xxx','xxx');
       my $rs = $dbh->prepare("select 1 from $table_access where 
username='$username' and passwd='$password'");
       $rs->execute;
       my ($result) = $rs->fetchrow_array;
       $rs->finish();
       $dbh->disconnect();

       if ($result){
               return Apache::OK;
       }
       $r->note_basic_auth_failure;
       return Apache::AUTH_REQUIRED;
}
1;
Any assistance on this issue would be greatly appreciated.