Use the nova diagnostics command to retrieve CPU, memory, I/O and network statistics from an instance:
$ nova diagnostics ubuntu
+------------------+---------------+
| Property | Value |
+------------------+---------------+
| cpu0_time | 1138410000000 |
| memory | 524288 |
| memory-actual | 524288 |
| memory-rss | 591664 |
| vda_errors | -1 |
| vda_read | 334864384 |
| vda_read_req | 13851 |
| vda_write | 2985382912 |
| vda_write_req | 177180 |
| vnet4_rx | 45381339 |
| vnet4_rx_drop | 0 |
| vnet4_rx_errors | 0 |
| vnet4_rx_packets | 106426 |
| vnet4_tx | 37513574 |
| vnet4_tx_drop | 0 |
| vnet4_tx_errors | 0 |
| vnet4_tx_packets | 162200 |
+------------------+---------------+
Use the nova usage-list command to get summary statistics for each tenant:
$ nova usage-list Usage from 2012-10-10 to 2012-11-08: +----------------------------------+-----------+--------------+-----------+---------------+ | Tenant ID | Instances | RAM MB-Hours | CPU Hours | Disk GB-Hours | +----------------------------------+-----------+--------------+-----------+---------------+ | 0eec5c34a7a24a7a8ddad27cb81d2706 | 8 | 240031.10 | 468.81 | 0.00 | | 92a5d9c313424537b78ae3e42858fd4e | 5 | 483568.64 | 236.12 | 0.00 | | f34d8f7170034280a42f6318d1a4af34 | 106 | 16888511.58 | 9182.88 | 0.00 | +----------------------------------+-----------+--------------+-----------+---------------+