Thanks a lot for your help. However, I got "Segmentation fault" with my real code. Then, I used "perl -d" and "s" command to step through all the sub routines. Looks like the failure is related to LibXML. Any idea how to make it work?

......

DB<1> s
XML::LibXML::Node::CLONE_SKIP(/usr/lib64/perl5/site_perl/5.8.8/x86_64-linux-thread-multi/XML/LibXML.pm:1249): 1249: return $XML::LibXML::__threads_shared ? 0 : 1;

DB<1> s
XML::LibXML::XPathContext::CLONE_SKIP(/usr/lib64/perl5/site_perl/5.8.8/x86_64-linux-thread-multi/XML/LibXML/XPathContext.pm:25): 25: sub CLONE_SKIP { 1 }

DB<1> s
XML::LibXML::CLONE_SKIP(/usr/lib64/perl5/site_perl/5.8.8/x86_64-linux-thread-multi/XML/LibXML.pm:414): 414: return $XML::LibXML::__threads_shared ? 0 : 1;

DB<1> s
XML::LibXML::SAX::CLONE_SKIP(/usr/lib64/perl5/site_perl/5.8.8/x86_64-linux-thread-multi/XML/LibXML/SAX.pm:26): 26: return $XML::LibXML::__threads_shared ? 0 : 1;

DB<1> s
Segmentation fault

I use the modules below.

use strict;
use warnings;
use Scalar::Util 'reftype';
use encoding "utf8";
use Data::Dumper;
use CGI qw(:standard Vars);
use LWP::UserAgent;
use XML::Simple;
use threads;

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In reply to Re^6: Parallel Modules ? by Gary Yang
in thread Parallel Modules ? by Gary Yang

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