# disk cache size will use a disk cache, sized to the
# container's RAM requirement (but with minimum 2 GiB and
# maximum 32 GiB).
+ #
+ # Note: If you change this value, containers that used the previous
+ # default value will only be reused by container requests that
+ # explicitly specify the previous value in their keep_cache_ram
+ # runtime constraint.
DefaultKeepCacheRAM: 0
# Number of times a container can be unlocked before being
# Container runtime: "docker" (default) or "singularity"
RuntimeEngine: docker
- # Number of "supervisor" containers eligible to run at any given
- # time expressed as a fraction of CloudVMs.MaxInstances. A
- # supervisor is a container who's purpose is to submit other
- # containers, such as a container running arvados-cwl-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.
- SupervisorFraction: 0.3
-
# When running a container, run a dedicated keepstore process,
# using the specified number of 64 MiB memory buffers per
# allocated CPU core (VCPUs in the container's runtime
# down.
MaxInstances: 64
+ # Maximum fraction of CloudVMs.MaxInstances 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
+
# Interval between cloud provider syncs/updates ("list all
# instances").
SyncInterval: 1m