So my original code contained the following.

my $twig = 'XML::Twig'->new;
$twig->xparse($input_xml);
[download]

And POJ's code contains the following.

my $twig = 'XML::Twig'->new( twig_handlers =>  { result => \&record })
+;
$twig->parse($input_xml);
[download]

POJ's code when I do 10000 records is blowing up in the Twig module as follows.

  DB<2> c
Exiting subroutine via next at vance.pl line 91.
 at vance.pl line 91.
    main::record(XML::Twig=HASH(0x6003ead30), XML::Twig::Elt=HASH(0x60
+2c20e90)) called at /usr/lib/perl5/site_perl/5.22/XML/Twig.pm line 23
+48
    XML::Twig::_twig_end(XML::Parser::Expat=HASH(0x6003fafe0), "result
+") called at /usr/lib/perl5/site_perl/5.22/x86_64-cygwin-threads/XML/
+Parser/Expat.pm line 474
    XML::Parser::Expat::parse(XML::Parser::Expat=HASH(0x6003fafe0), "<
+?xml version=\"1.0\" encoding=\"UTF-8\"?><response><result><chec"...)
+ called at /usr/lib/perl5/site_perl/5.22/x86_64-cygwin-threads/XML/Pa
+rser.pm line 187
    eval {...} called at /usr/lib/perl5/site_perl/5.22/x86_64-cygwin-t
+hreads/XML/Parser.pm line 186
    XML::Parser::parse(XML::Twig=HASH(0x6003ead30), "<?xml version=\"1
+.0\" encoding=\"UTF-8\"?><response><result><chec"...) called at /usr/
+lib/perl5/site_perl/5.22/XML/Twig.pm line 767
    eval {...} called at /usr/lib/perl5/site_perl/5.22/XML/Twig.pm lin
+e 767
    XML::Twig::parse(XML::Twig=HASH(0x6003ead30), "<?xml version=\"1.0
+\" encoding=\"UTF-8\"?><response><result><chec"...) called at vance.p
+l line 33
Exiting subroutine via next at vance.pl line 91.
[download]

It is deep in the Twig module when I single step, but I think its tied to some sort of overflow condition. Any ideas as to how to fix this? POJ, why did you change those lines? Here is the current code.

use strict;
use warnings;
use XML::Twig;
use Text::CSV;
use Data::Dump 'pp';
use Data::Dumper;
use REST::Client;
use MIME::Base64;
use Text::Unidecode;
use utf8;

my @header   = ();
my @csv_rows = ();
my $order_by = 'u_ci_id';

my %seen = ();
my %arx_data = ();

# parse xml in chunks
my $twig = 'XML::Twig'->new( twig_handlers =>  { result => \&record })
+;
my $client = REST::Client->new(host => 'https://staplessb.service-now.
+com');
my $encoded_auth = encode_base64("1774580:Natalie1", '');

$client->GET("/api/now/table/cmdb_ci?sysparm_limit=10000",

                {'Authorization' => "Basic $encoded_auth",

                 'Accept' => 'application/xml'});

my $input_xml = $client->responseContent();

$twig->parse($input_xml);

# data dump
pp \%arx_data;
#pp \@csv_rows;
#pp \@header;

# sort and dump csv
my @sorted = sort { $b->[0] cmp $a->[0] } @csv_rows;
unshift @sorted,[@header]; # add header

my $outfile = 'xmldump.csv';
my $csv = Text::CSV->new ( { binary => 1 } )  
    or die "Cannot use CSV: ".Text::CSV->error_diag ();
$csv->eol("\n"); 

if ($outfile){        
  open my $fh, ">:encoding(utf8)", $outfile or die "$outfile: $!";
  for (@sorted){
    shift @$_; # remove sort field
    $csv->print ($fh, $_);
  }
  close $fh or die "new.csv: $!"; 
} else {
  for (@sorted){
    shift @$_;
    $csv->print (\*STDOUT, $_);
  }
}  

# parse 1 record
sub record {
  my ($e,$t) = @_;
  
  # csv records
  unless (@header){
    my @info_tags = $t->children;
    @header = map{ $_->name } @info_tags;
    unshift @header,$order_by; # add sort field
  }
  
  # extract data in same order as header row
  my @data = map{ $t->field($_) } @header;
  push @csv_rows,clean(@data); #returns array ref
 
  # build hash structure
  my $app   = $t->field('u_application_id');
  my $u_ci  = $t->field('u_ci_id');
  my $class = $t->field('sys_class_name');
  my $name  = $t->field('name');
  my $ip    = $t->field('ip_address');
  my $fqdn  = $t->field('fqdn');
  my $dns   = $t->field('dns_domain');
  my $mac   = $t->field('mac');
  
  if ( $class eq 'cmdb_ci_appl'){
    $arx_data{$u_ci}{'name'} = $name;  
  } else {
    next if $seen{$app}{$ip}++;
    push @{$arx_data{$app}{'members'}},$ip;
  }
  
}

sub clean {
  my @f = @_;
  for (@f){
    s/\r|\n//g;  # Cleanup Carraige Returns
    s/, / /g;    # Cleanup Comma Space
    s/,/ /g;     # Cleanup Comma
    s/"//g;      # Cleanup Parentheses
    s/^\s+|\s+$//g;    # Trim spaces
    s/([^[:ascii:]]+)/unidecode($1)/ge;
  }
  return \@f;
}
[download]