Scheduler Service
Bases: nova.manager.Manager
Chooses a host to run instances on.
Get the normalized set of capabilites for this zone, or for a particular service.
Get a list of zones from the ZoneManager.
Poll child zones periodically to get status.
Shows the physical/usage resource given by hosts.
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Returns: | example format is below. {‘resource’:D, ‘usage’:{proj_id1:D, proj_id2:D}} D: {‘vcpus’:3, ‘memory_mb’:2048, ‘local_gb’:2048} |
Process a capability update from a service node.
Scheduler base class that all Schedulers should inherit from
Bases: nova.exception.Error
There is no valid host for the command.
Bases: object
The base class that all Scheduler clases should inherit from.
Checks if destination host has enough resource for live migration.
Currently, only memory checking has been done. If storage migration(block migration, meaning live-migration without any shared storage) will be available, local storage checking is also necessary.
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Return the list of hosts that have a running service for topic.
Check if the src and dest host mount same shared storage.
At first, dest host creates temp file, and src host can see it if they mounts same shared storage. Then src host erase it.
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Must override at least this method for scheduler to work.
Live migration scheduling method.
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Returns: | The host where instance is running currently. Then scheduler send request that host. |
Check whether a service is up based on last heartbeat.
Called by the Scheduler Service to supply a ZoneManager.
Bases: nova.exception.Error
The specified host is not up or doesn’t exist.
Chance (Random) Scheduler implementation
Bases: nova.scheduler.driver.Scheduler
Implements Scheduler as a random node selector.
Picks a host that is up at random.
Simple Scheduler
Bases: nova.scheduler.chance.ChanceScheduler
Implements Naive Scheduler that tries to find least loaded host.
Picks a host that is up and has the fewest volumes.
Picks a host that is up and has the fewest running instances.
Picks a host that is up and has the fewest networks.