I'm not sure if I understand your requirement exactly, but here is a way to extract the values using XML::LibXML and Xpaths: 
use XML::LibXML;

my $doc = XML::LibXML->load_xml(string => $xml);
my @mds = $doc->findnodes('//md');
for my $md ( @mds ) {
    my @mts = $md->findnodes('mi/mt');
    next unless @mts;
    my @rs = $md->findnodes('mi/mv/r');
    for my $i ( 0 .. $#mts ) {
        my ( $mt, $r ) = ( $mts[$i], $rs[$i] );
        print "mt: ", $mt->textContent, "\n";
        print "r: ", $r->textContent, "\n\n";
    }
}

[download]
Output using your example XML: 
mt: pmPdcpPktDiscDlEth
r: 0

mt: pmLicDlCapActual
r: 0

mt: pmLicUlCapActual
r: 0

mt: pmLicDlPrbCapActual
r: 0

mt: pmLicUlPrbCapActual
r: 0

mt: pmPdcpPktDiscDlEth
r: 0

mt: pmPdcpPktDiscUlEthPacing
r: 0

mt: pmLicDlCapDistr
r: 81893,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

mt: pmLicUlCapDistr
r: 90083,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

mt: pmLicDlPrbCapDistr
r: 81893,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

mt: pmLicUlPrbCapDistr
r: 90083,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

[download]

In reply to Re: Extract Data from XML (unique xml format?) by tangent
in thread Extract Data from XML (unique xml format?) by clapeters

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