Upstart Job Groups

1
Upstart Job Groups

• V2
• Sarvi Shanmugham

2
Upstart Job Groups

• Each Group has a Group Behavior Definition
• Defines how the group jobs affect group state
• More Group Level attributes TBD here based on
  future needs
• Group definitions could be in a separate
  directory /etc/init.d/groups
• Individual Jobs in their definition can choose to
  join a group as
• a member
• All Member jobs get affected during a group
  operation.
• a trigger
• Trigger jobs affect the group. They may or may
  not be part of the group itself.
• Trigger to restart group for now. Other triggered
  operations TBD as needed.

3
New Stanzas Definition

• A Group File Stanza
• This stanza defines it to be a group job and
  specifies how individual members affect the
  combined group state
• group-state ANDOR
• Individual Job File Stanzas
• This stanza allows for a modular job file
  definition. Values in the file augment and
  override the main file.
• include ltjob-file.includegt
• This stanza is specified in the individual job
  files when the job should be a member of a group.
  A job can be part of more than one group
• group-member ltgroup-namegt
• This stanza is specified in the individual job
  files when the job should be a trigger to a group
  operation. A job can be a trigger for more than
  one group.
• group-trigger ltgroup-namegt
• This stanza sets a jobs initial config state.
  Default value enabled. Config state affects if
  a job will be started when its startup conditions
  are met.
• config-state disabledenabledoptional

4
Group State

• Group state simply combines the states of the
  group members as defined by the group-state
  stanza.
• AND combines the member states as
• while job1 and job2 and job3.
• OR - combines the member states as
• while job1 or job2 or job3

5
Upstart Operations/API Enhancements

• Most individual job operations can be done on a
  group-name and will translate to that operation
  being applied to all jobs in the group.
• Start
• Translates to a START to all jobs in the group
• Stop
• Translates to a STOP to all jobs in the group
• Restart
• Translates to a RESTART to all jobs in the group.
  This happens in parallel to all jobs in the
  group. Does not guarantee restart order within
  the group
• State-Subscribe
• Translates to a state-subscribe to all the
  individual jobs in the group. The same command
  can also be used to subscribed to the group state
  only, if needed
• Config-State Enable/Disable
• Translates to a Enable/Disable of the config
  state of the job.