> If your pollster is not running to compute delta and you have > no state stored, you'll miss a part of what has been used.
Would we have also have some 'misses' with the cumulative approach when the ceilometer agent was down? If I understood the (\Sigma local maxima)-first idea correctly, the usage up to the first polling cycle would always be discounted from any duration. Similarly, calculating the time delta as a gauge measure would discount only the usage up to the first libvirt poll after each ceilo agent restart. As long as the ceilo compute agent was restarted only rarely, I'm not sure the under-reporting would be a huge issue in either case. A more pernicious problem would occur if the instance was being regularly restarted with a higher frequency than the polling period. Cheers, Eoghan _______________________________________________ Mailing list: https://launchpad.net/~openstack Post to : openstack@lists.launchpad.net Unsubscribe : https://launchpad.net/~openstack More help : https://help.launchpad.net/ListHelp
