[MESOS-3891] Add a helper function to the Agent to check available resources before launching a task.

• Type: Bug
• Status: Accepted
• Priority: Major
• Resolution: Unresolved
• Labels: mesosphere
• Epic Link: oversubscription for reservation
• Story Points: 5
• Assignee: Guangya Liu
• Reporter: Artem Harutyunyan
• Created: 11/Nov/15 13:23
• Updated: 26/Nov/18 13:36

Description

Launching a task using revocable resources should be funnelled through an accounting system:

• If a task is launched using revocable resources, the resources must not be in use when launching the task. If they are in use, then the task should fail to start.
• If a task is launched using reserved resources, the resources must be made available. This means potentially evicting tasks which are using revocable resources.

Both cases could be implemented by adding a check in Slave::runTask, like a new helper method:

class Slave {
  ...
  // Checks if the given resources are available (i.e. not utilized)
  // for starting a task.  If not, the task should either fail to
  // start or result in the eviction of revocable resources.
  virtual process::Future<bool> checkAvailableResources(
      const Resources& resources);
  ...
}