<?php $id = new MongoId(); if (getmypid() <= 65536) { $retval = $id->getPid() == getmypid(); } else { $retval = true; } var_dump($id->getPid(), $id->__toString(), $retval); $id = new MongoID("4fe3420a44415ecc83000000"); var_dump($id->getPid(), $id->__toString()); $id = new MongoID("4fe3427744415e4f84000001"); var_dump($id->getPid(), $id->__toString()); $id = new MongoID("4fe342a944415e5284000000"); var_dump($id->getPid(), $id->__toString());