17.3. Monitoring and Diagnostics
You can use xm to perform a memory dump of an existing virtual machine.
xm dump-core [-C] [domain-id]
This command dumps the virtual machine's memory to the xendump file located in the /var/xen/dump/ directory. You can terminate the virtual machine by including the -C option.
You can use xm to monitor domains and hosts in real time:
xm top [domain-id]
You can use xm to display the domain activity states of one or more domains:
xm list [domain-id] [ ——long | ——label]
You can specify a specific domain(s) by name (s). The [——long] option provides a more detailed breakdown of the domain you specified. The [——label] domain adds an additional column that displays label status. The outputs displays:
Name ID Mem(MiB) VCPUs State Time Label ———————————————— Domain0 0 927 8 r—————— 204.9 INACTIVE Domain202 1 927 8 s—————— 205.0/command ACTIVE DomainQ/A 2 927 8 b—————— INACTIVE Domain9600 3 927 8 c—————— 205.1 ACTIVE
Here are the six domain states per VCPU:
| State | Description |
|---|---|
|
running |
lists domains currently active on a CPU |
|
blocked |
lists domains that are blocked (a domain becomes blocked when the vcpu is awaiting for an external event to happen) |
|
paused |
lists domains that are suspended |
|
shutdown |
lists domains that are in process of shutting down |
|
shutoff |
lists domains that are completely down. |
|
crashed |
lists domains that are crashed |
|
inactive |
lists domains that are inactive instances |
|
——all |
lists domains that are both active and inactive vcpu instances |
Table 17.3. The Domain States