+ # The minimum number of instances expected to be runnable
+ # without reaching a provider-imposed quota.
+ #
+ # This is used as the initial value for the dispatcher's
+ # dynamic instance limit, which increases (up to MaxInstances)
+ # as containers start up successfully and decreases in
+ # response to high API load and cloud quota errors.
+ #
+ # Setting this too high creates a risk that the dispatcher
+ # will cause deadlock by starting so many supervisor
+ # containers (based on SupervisorFraction and MaxInstances)
+ # that the cloud quota prevents them from running any child
+ # containers.
+ #
+ # Setting this too low causes the dispatcher to be
+ # unnecessarily slow to start up new instances after a
+ # restart.
+ InitialQuotaEstimate: 16
+
+ # Maximum fraction of available instance capacity allowed to
+ # run "supervisor" containers at any given time. A supervisor
+ # is a container whose purpose is mainly to submit and manage
+ # other containers, such as arvados-cwl-runner workflow
+ # runner.
+ #
+ # If there is a hard limit on the amount of concurrent
+ # containers that the cluster can run, it is important to
+ # avoid crowding out the containers doing useful work with
+ # containers who just create more work.
+ #
+ # For example, with the default MaxInstances of 64, it will
+ # schedule at most floor(64*0.30) = 19 concurrent workflows,
+ # ensuring 45 slots are available for work.
+ SupervisorFraction: 0.30
+