Man pages matching name rrdtool::oo in section 3pm:

RRDTool::OO.3pm.en	debian 10 / librrdtool-oo-perl
RRDTool::OO.3pm.en	debian 11 / librrdtool-oo-perl
RRDTool::OO.3pm.en	debian 12 / librrdtool-oo-perl