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Description

This module creates a slurm controller node via the slurm-gcp slurm_controller_instance and slurm_instance_template modules.

More information about Slurm On GCP can be found at the project's GitHub page and in the Slurm on Google Cloud User Guide.

The user guide provides detailed instructions on customizing and enhancing the Slurm on GCP cluster as well as recommendations on configuring the controller for optimal performance at different scales.

Example

- id: slurm_controller
  source: community/modules/scheduler/schedmd-slurm-gcp-v6-controller
  use:
  - network
  - homefs
  - compute_partition
  settings:
    machine_type: c2-standard-8

This creates a controller node with the following attributes:

  • connected to the primary subnetwork of network
  • the filesystem with the ID homefs (defined elsewhere in the blueprint) mounted
  • One partition with the ID compute_partition (defined elsewhere in the blueprint)
  • machine type upgraded from the default c2-standard-4 to c2-standard-8

Live Cluster Reconfiguration

The schedmd-slurm-gcp-v6-controller module supports the reconfiguration of partitions and slurm configuration in a running, active cluster.

To reconfigure a running cluster:

  1. Edit the blueprint with the desired configuration changes
  2. Call gcluster create <blueprint> -w to overwrite the deployment directory
  3. Follow instructions in terminal to deploy

The following are examples of updates that can be made to a running cluster:

  • Add or remove a partition to the cluster
  • Resize an existing partition
  • Attach new network storage to an existing partition

NOTE: Changing the VM machine_type of a partition may not work. It is better to create a new partition and delete the old one.

Custom Images

For more information on creating valid custom images for the controller VM instance or for custom instance templates, see our vm-images.md documentation page.

GPU Support

More information on GPU support in Slurm on GCP and other Cluster Toolkit modules can be found at docs/gpu-support.md

Reservation for Scheduled Maintenance

A maintenance event is when a compute engine stops a VM to perform a hardware or software update which is determined by the host maintenance policy. This can also affect the running jobs if the maintenance kicks in. Now, Customers can protect jobs from getting terminated due to maintenance using the cluster toolkit. You can enable creation of reservation for scheduled maintenance for your compute nodeset and Slurm will reserve your node for maintenance during the maintenance window. If you try to schedule any jobs which overlap with the maintenance reservation, Slurm would not schedule any job.

You can specify in your blueprint like

  - id: compute_nodeset
    source: community/modules/compute/schedmd-slurm-gcp-v6-nodeset
    use: [network]
    settings:
      enable_maintenance_reservation: true

To enable creation of reservation for maintenance.

While running job on slurm cluster, you can specify total run time of the job using -t flag.This would only run the job outside of the maintenance window.

srun -n1 -pcompute -t 10:00 <job.sh>

Currently upcoming maintenance notification is supported in ALPHA version of compute API. You can update the API version from your blueprint,

  - id: slurm_controller
    source: community/modules/scheduler/schedmd-slurm-gcp-v6-controller
    settings:
      endpoint_versions:
        compute: "alpha"

Opportunistic GCP maintenance in Slurm

Customers can also enable running GCP maintenance as Slurm job opportunistically to perform early maintenance. If a node is detected for maintenance, Slurm will create a job to perform maintenance and put it in the job queue.

If backfill scheduler is used, Slurm will backfill maintenance job if it can find any empty time window.

Customer can also choose builtin scheduler type. In this case, Slurm would run maintenance job in strictly priority order. If the maintenance job doesn't kick in, then forced maintenance will take place at scheduled window.

Customer can enable this feature at nodeset level by,

  - id: debug_nodeset
    source: community/modules/compute/schedmd-slurm-gcp-v6-nodeset
    use: [network]
    settings:
      enable_opportunistic_maintenance: true

Placement Max Distance

When using enable_placement with Slurm, Google Compute Engine will attempt to place VMs as physically close together as possible. Capacity constraints at the time of VM creation may still force VMs to be spread across multiple racks. Google provides the max-distance flag which can used to control the maximum spreading allowed. Read more about max-distance in the official docs.

You can use the enable_slurm_gcp_plugins.max_hops.max_hops setting on the controller module to control the max-distance behavior. See the following example:

  - id: controller
    source: community/modules/scheduler/schedmd-slurm-gcp-v6-controller
    use: [ network, partition ]
    settings:
      enable_slurm_gcp_plugins:
        max_hops:
          max_hops: 1

Note

schedmd-slurm-gcp-v6-nodeset.settings.enable_placement: true must also be set for max-distance to take effect.

In the above case using a value of 1 will restrict VM to be placed on the same rack. You can confirm that the max-distance was applied by calling the following command while jobs are running:

gcloud beta compute resource-policies list \
  --format='yaml(name,groupPlacementPolicy.maxDistance)'

Warning

If a zone lacks capacity, using a lower max-distance value (such as 1) is more likely to cause VMs creation to fail.

TreeWidth and Node Communication

Slurm uses a fan out mechanism to communicate large groups of nodes. The shape of this fan out tree is determined by the TreeWidth configuration variable.

In the cloud, this fan out mechanism can become unstable when nodes restart with new IP addresses. You can enforce that all nodes communicate directly with the controller by setting TreeWidth to a value >= largest partition.

If the largest partition was 200 nodes, configure the blueprint as follows:

  - id: slurm_controller
    source: community/modules/scheduler/schedmd-slurm-gcp-v5-controller
    ...
    settings:
      cloud_parameters:
        tree_width: 200

The default has been set to 128. Values above this have not been fully tested and may cause congestion on the controller. A more scalable solution is under way.

Hybrid Slurm Clusters

For more information on how to configure an on premise slurm cluster with hybrid cloud partitions, see the schedmd-slurm-gcp-v5-hybrid module and our extended instructions in our docs.

Support

The Cluster Toolkit team maintains the wrapper around the slurm-on-gcp terraform modules. For support with the underlying modules, see the instructions in the slurm-gcp README.

License

Copyright 2023 Google LLC

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Requirements

Name Version
terraform >= 1.3
google >= 4.84

Providers

Name Version
google >= 4.84

Modules

Name Source Version
bucket terraform-google-modules/cloud-storage/google ~> 6.1
daos_network_storage_scripts ../../../../modules/scripts/startup-script n/a
nodeset_cleanup ./modules/cleanup_compute n/a
nodeset_cleanup_tpu ./modules/cleanup_tpu n/a
slurm_controller_template github.com/GoogleCloudPlatform/slurm-gcp.git//terraform/slurm_cluster/modules/slurm_instance_template 6.8.6
slurm_files ./modules/slurm_files n/a
slurm_login_instance github.com/GoogleCloudPlatform/slurm-gcp.git//terraform/slurm_cluster/modules/_slurm_instance 6.8.6
slurm_login_template github.com/GoogleCloudPlatform/slurm-gcp.git//terraform/slurm_cluster/modules/slurm_instance_template 6.8.6
slurm_nodeset_template github.com/GoogleCloudPlatform/slurm-gcp.git//terraform/slurm_cluster/modules/slurm_instance_template 6.8.6
slurm_nodeset_tpu github.com/GoogleCloudPlatform/slurm-gcp.git//terraform/slurm_cluster/modules/slurm_nodeset_tpu 6.8.6

Resources

Name Type
google_compute_instance_from_template.controller resource
google_secret_manager_secret.cloudsql resource
google_secret_manager_secret_iam_member.cloudsql_secret_accessor resource
google_secret_manager_secret_version.cloudsql_version resource
google_storage_bucket_iam_binding.legacy_readers resource
google_storage_bucket_iam_binding.viewers resource
google_compute_image.slurm data source
google_project.this data source

Inputs

Name Description Type Default Required
additional_disks List of maps of disks.
list(object({
disk_name = string
device_name = string
disk_type = string
disk_size_gb = number
disk_labels = map(string)
auto_delete = bool
boot = bool
}))
[] no
allow_automatic_updates If false, disables automatic system package updates on the created instances. This feature is
only available on supported images (or images derived from them). For more details, see
https://cloud.google.com/compute/docs/instances/create-hpc-vm#disable_automatic_updates
bool true no
bandwidth_tier Configures the network interface card and the maximum egress bandwidth for VMs.
- Setting platform_default respects the Google Cloud Platform API default values for networking.
- Setting virtio_enabled explicitly selects the VirtioNet network adapter.
- Setting gvnic_enabled selects the gVNIC network adapter (without Tier 1 high bandwidth).
- Setting tier_1_enabled selects both the gVNIC adapter and Tier 1 high bandwidth networking.
- Note: both gVNIC and Tier 1 networking require a VM image with gVNIC support as well as specific VM families and shapes.
- See official docs for more details.
string "platform_default" no
bucket_dir Bucket directory for cluster files to be put into. If not specified, then one will be chosen based on slurm_cluster_name. string null no
bucket_name Name of GCS bucket.
Ignored when 'create_bucket' is true.
string null no
can_ip_forward Enable IP forwarding, for NAT instances for example. bool false no
cgroup_conf_tpl Slurm cgroup.conf template file path. string null no
cloud_parameters cloud.conf options. Defaults inherited from Slurm GCP repo
object({
no_comma_params = optional(bool, false)
private_data = optional(list(string))
scheduler_parameters = optional(list(string))
resume_rate = optional(number)
resume_timeout = optional(number)
suspend_rate = optional(number)
suspend_timeout = optional(number)
topology_plugin = optional(string)
topology_param = optional(string)
tree_width = optional(number)
})
{} no
cloudsql Use this database instead of the one on the controller.
server_ip : Address of the database server.
user : The user to access the database as.
password : The password, given the user, to access the given database. (sensitive)
db_name : The database to access.
user_managed_replication : The list of location and (optional) kms_key_name for secret
object({
server_ip = string
user = string
password = string # sensitive
db_name = string
user_managed_replication = optional(list(object({
location = string
kms_key_name = optional(string)
})), [])
})
null no
compute_startup_script Startup script used by the compute VMs. string "# no-op" no
compute_startup_scripts_timeout The timeout (seconds) applied to each script in compute_startup_scripts. If
any script exceeds this timeout, then the instance setup process is considered
failed and handled accordingly.

NOTE: When set to 0, the timeout is considered infinite and thus disabled.
number 300 no
controller_startup_script Startup script used by the controller VM. string "# no-op" no
controller_startup_scripts_timeout The timeout (seconds) applied to each script in controller_startup_scripts. If
any script exceeds this timeout, then the instance setup process is considered
failed and handled accordingly.

NOTE: When set to 0, the timeout is considered infinite and thus disabled.
number 300 no
create_bucket Create GCS bucket instead of using an existing one. bool true no
deployment_name Name of the deployment. string n/a yes
disable_controller_public_ips DEPRECATED: Use enable_controller_public_ips instead. bool null no
disable_default_mounts DEPRECATED: Use enable_default_mounts instead. bool null no
disable_smt DEPRECATED: Use enable_smt instead. bool null no
disk_auto_delete Whether or not the boot disk should be auto-deleted. bool true no
disk_labels Labels specific to the boot disk. These will be merged with var.labels. map(string) {} no
disk_size_gb Boot disk size in GB. number 50 no
disk_type Boot disk type, can be either hyperdisk-balanced, pd-ssd, pd-standard, pd-balanced, or pd-extreme. string "pd-ssd" no
enable_bigquery_load Enables loading of cluster job usage into big query.

NOTE: Requires Google Bigquery API.
bool false no
enable_cleanup_compute Enables automatic cleanup of compute nodes and resource policies (e.g.
placement groups) managed by this module, when cluster is destroyed.

WARNING: Toggling this off will impact the running workload.
Deployed compute nodes will be destroyed.
bool true no
enable_confidential_vm Enable the Confidential VM configuration. Note: the instance image must support option. bool false no
enable_controller_public_ips If set to true. The controller will have a random public IP assigned to it. Ignored if access_config is set. bool false no
enable_debug_logging Enables debug logging mode. bool false no
enable_default_mounts Enable default global network storage from the controller
- /home
- /apps
Warning: If these are disabled, the slurm etc and munge dirs must be added
manually, or some other mechanism must be used to synchronize the slurm conf
files and the munge key across the cluster.
bool true no
enable_devel DEPRECATED: enable_devel is always on. bool null no
enable_external_prolog_epilog Automatically enable a script that will execute prolog and epilog scripts
shared by NFS from the controller to compute nodes. Find more details at:
https://github.com/GoogleCloudPlatform/slurm-gcp/blob/master/tools/prologs-epilogs/README.md
bool null no
enable_oslogin Enables Google Cloud os-login for user login and authentication for VMs.
See https://cloud.google.com/compute/docs/oslogin
bool true no
enable_shielded_vm Enable the Shielded VM configuration. Note: the instance image must support option. bool false no
enable_slurm_gcp_plugins Enables calling hooks in scripts/slurm_gcp_plugins during cluster resume and suspend. any false no
enable_smt Enables Simultaneous Multi-Threading (SMT) on instance. bool false no
endpoint_versions Version of the API to use (The compute service is the only API currently supported)
object({
compute = string
})
{
"compute": "beta"
}
no
epilog_scripts List of scripts to be used for Epilog. Programs for the slurmd to execute
on every node when a user's job completes.
See https://slurm.schedmd.com/slurm.conf.html#OPT_Epilog.
list(object({
filename = string
content = optional(string)
source = optional(string)
}))
[] no
extra_logging_flags The only available flag is trace_api map(bool) {} no
gcloud_path_override Directory of the gcloud executable to be used during cleanup string "" no
guest_accelerator List of the type and count of accelerator cards attached to the instance.
list(object({
type = string,
count = number
}))
[] no
instance_image Defines the image that will be used in the Slurm controller VM instance.

Expected Fields:
name: The name of the image. Mutually exclusive with family.
family: The image family to use. Mutually exclusive with name.
project: The project where the image is hosted.

For more information on creating custom images that comply with Slurm on GCP
see the "Slurm on GCP Custom Images" section in docs/vm-images.md.
map(string)
{
"family": "slurm-gcp-6-8-hpc-rocky-linux-8",
"project": "schedmd-slurm-public"
}
no
instance_image_custom A flag that designates that the user is aware that they are requesting
to use a custom and potentially incompatible image for this Slurm on
GCP module.

If the field is set to false, only the compatible families and project
names will be accepted. The deployment will fail with any other image
family or name. If set to true, no checks will be done.

See: https://goo.gle/hpc-slurm-images
bool false no
instance_template DEPRECATED: Instance template can not be specified for controller. string null no
labels Labels, provided as a map. map(string) {} no
login_network_storage An array of network attached storage mounts to be configured on all login nodes.
list(object({
server_ip = string,
remote_mount = string,
local_mount = string,
fs_type = string,
mount_options = string,
}))
[] no
login_nodes List of slurm login instance definitions.
list(object({
name_prefix = string
access_config = optional(list(object({
nat_ip = string
network_tier = string
})))
additional_disks = optional(list(object({
disk_name = optional(string)
device_name = optional(string)
disk_size_gb = optional(number)
disk_type = optional(string)
disk_labels = optional(map(string), {})
auto_delete = optional(bool, true)
boot = optional(bool, false)
})), [])
additional_networks = optional(list(object({
access_config = optional(list(object({
nat_ip = string
network_tier = string
})), [])
alias_ip_range = optional(list(object({
ip_cidr_range = string
subnetwork_range_name = string
})), [])
ipv6_access_config = optional(list(object({
network_tier = string
})), [])
network = optional(string)
network_ip = optional(string, "")
nic_type = optional(string)
queue_count = optional(number)
stack_type = optional(string)
subnetwork = optional(string)
subnetwork_project = optional(string)
})), [])
bandwidth_tier = optional(string, "platform_default")
can_ip_forward = optional(bool, false)
disable_smt = optional(bool, false)
disk_auto_delete = optional(bool, true)
disk_labels = optional(map(string), {})
disk_size_gb = optional(number)
disk_type = optional(string, "n1-standard-1")
enable_confidential_vm = optional(bool, false)
enable_oslogin = optional(bool, true)
enable_shielded_vm = optional(bool, false)
gpu = optional(object({
count = number
type = string
}))
labels = optional(map(string), {})
machine_type = optional(string)
metadata = optional(map(string), {})
min_cpu_platform = optional(string)
num_instances = optional(number, 1)
on_host_maintenance = optional(string)
preemptible = optional(bool, false)
region = optional(string)
service_account = optional(object({
email = optional(string)
scopes = optional(list(string), ["https://www.googleapis.com/auth/cloud-platform"])
}))
shielded_instance_config = optional(object({
enable_integrity_monitoring = optional(bool, true)
enable_secure_boot = optional(bool, true)
enable_vtpm = optional(bool, true)
}))
source_image_family = optional(string)
source_image_project = optional(string)
source_image = optional(string)
static_ips = optional(list(string), [])
subnetwork = string
spot = optional(bool, false)
tags = optional(list(string), [])
zone = optional(string)
termination_action = optional(string)
}))
[] no
login_startup_script Startup script used by the login VMs. string "# no-op" no
login_startup_scripts_timeout The timeout (seconds) applied to each script in login_startup_scripts. If
any script exceeds this timeout, then the instance setup process is considered
failed and handled accordingly.

NOTE: When set to 0, the timeout is considered infinite and thus disabled.
number 300 no
machine_type Machine type to create. string "c2-standard-4" no
metadata Metadata, provided as a map. map(string) {} no
min_cpu_platform Specifies a minimum CPU platform. Applicable values are the friendly names of
CPU platforms, such as Intel Haswell or Intel Skylake. See the complete list:
https://cloud.google.com/compute/docs/instances/specify-min-cpu-platform
string null no
network_storage An array of network attached storage mounts to be configured on all instances.
list(object({
server_ip = string,
remote_mount = string,
local_mount = string,
fs_type = string,
mount_options = string,
client_install_runner = optional(map(string))
mount_runner = optional(map(string))
}))
[] no
nodeset Define nodesets, as a list.
list(object({
node_count_static = optional(number, 0)
node_count_dynamic_max = optional(number, 1)
node_conf = optional(map(string), {})
nodeset_name = string
additional_disks = optional(list(object({
disk_name = optional(string)
device_name = optional(string)
disk_size_gb = optional(number)
disk_type = optional(string)
disk_labels = optional(map(string), {})
auto_delete = optional(bool, true)
boot = optional(bool, false)
})), [])
bandwidth_tier = optional(string, "platform_default")
can_ip_forward = optional(bool, false)
disable_smt = optional(bool, false)
disk_auto_delete = optional(bool, true)
disk_labels = optional(map(string), {})
disk_size_gb = optional(number)
disk_type = optional(string)
enable_confidential_vm = optional(bool, false)
enable_placement = optional(bool, false)
enable_oslogin = optional(bool, true)
enable_shielded_vm = optional(bool, false)
enable_maintenance_reservation = optional(bool, false)
enable_opportunistic_maintenance = optional(bool, false)
gpu = optional(object({
count = number
type = string
}))
dws_flex = object({
enabled = bool
max_run_duration = number
use_job_duration = bool
})
labels = optional(map(string), {})
machine_type = optional(string)
maintenance_interval = optional(string)
instance_properties_json = string
metadata = optional(map(string), {})
min_cpu_platform = optional(string)
network_tier = optional(string, "STANDARD")
network_storage = optional(list(object({
server_ip = string
remote_mount = string
local_mount = string
fs_type = string
mount_options = string
client_install_runner = optional(map(string))
mount_runner = optional(map(string))
})), [])
on_host_maintenance = optional(string)
preemptible = optional(bool, false)
region = optional(string)
service_account = optional(object({
email = optional(string)
scopes = optional(list(string), ["https://www.googleapis.com/auth/cloud-platform"])
}))
shielded_instance_config = optional(object({
enable_integrity_monitoring = optional(bool, true)
enable_secure_boot = optional(bool, true)
enable_vtpm = optional(bool, true)
}))
source_image_family = optional(string)
source_image_project = optional(string)
source_image = optional(string)
subnetwork_self_link = string
additional_networks = optional(list(object({
network = string
subnetwork = string
subnetwork_project = string
network_ip = string
nic_type = string
stack_type = string
queue_count = number
access_config = list(object({
nat_ip = string
network_tier = string
}))
ipv6_access_config = list(object({
network_tier = string
}))
alias_ip_range = list(object({
ip_cidr_range = string
subnetwork_range_name = string
}))
})))
access_config = optional(list(object({
nat_ip = string
network_tier = string
})))
spot = optional(bool, false)
tags = optional(list(string), [])
termination_action = optional(string)
reservation_name = optional(string)
startup_script = optional(list(object({
filename = string
content = string })), [])

zone_target_shape = string
zone_policy_allow = set(string)
zone_policy_deny = set(string)
}))
[] no
nodeset_dyn Defines dynamic nodesets, as a list.
list(object({
nodeset_name = string
nodeset_feature = string
}))
[] no
nodeset_tpu Define TPU nodesets, as a list.
list(object({
node_count_static = optional(number, 0)
node_count_dynamic_max = optional(number, 5)
nodeset_name = string
enable_public_ip = optional(bool, false)
node_type = string
accelerator_config = optional(object({
topology = string
version = string
}), {
topology = ""
version = ""
})
tf_version = string
preemptible = optional(bool, false)
preserve_tpu = optional(bool, false)
zone = string
data_disks = optional(list(string), [])
docker_image = optional(string, "")
network_storage = optional(list(object({
server_ip = string
remote_mount = string
local_mount = string
fs_type = string
mount_options = string
client_install_runner = optional(map(string))
mount_runner = optional(map(string))
})), [])
subnetwork = string
service_account = optional(object({
email = optional(string)
scopes = optional(list(string), ["https://www.googleapis.com/auth/cloud-platform"])
}))
project_id = string
reserved = optional(string, false)
}))
[] no
on_host_maintenance Instance availability Policy. string "MIGRATE" no
partitions Cluster partitions as a list. See module slurm_partition.
list(object({
partition_name = string
partition_conf = optional(map(string), {})
partition_nodeset = optional(list(string), [])
partition_nodeset_dyn = optional(list(string), [])
partition_nodeset_tpu = optional(list(string), [])
enable_job_exclusive = optional(bool, false)
}))
n/a yes
preemptible Allow the instance to be preempted. bool false no
project_id Project ID to create resources in. string n/a yes
prolog_scripts List of scripts to be used for Prolog. Programs for the slurmd to execute
whenever it is asked to run a job step from a new job allocation.
See https://slurm.schedmd.com/slurm.conf.html#OPT_Prolog.
list(object({
filename = string
content = optional(string)
source = optional(string)
}))
[] no
region The default region to place resources in. string n/a yes
service_account DEPRECATED: Use service_account_email and service_account_scopes instead.
object({
email = string
scopes = set(string)
})
null no
service_account_email Service account e-mail address to attach to the controller instance. string null no
service_account_scopes Scopes to attach to the controller instance. set(string)
[
"https://www.googleapis.com/auth/cloud-platform"
]
no
shielded_instance_config Shielded VM configuration for the instance. Note: not used unless
enable_shielded_vm is 'true'.
enable_integrity_monitoring : Compare the most recent boot measurements to the
integrity policy baseline and return a pair of pass/fail results depending on
whether they match or not.
enable_secure_boot : Verify the digital signature of all boot components, and
halt the boot process if signature verification fails.
enable_vtpm : Use a virtualized trusted platform module, which is a
specialized computer chip you can use to encrypt objects like keys and
certificates.
object({
enable_integrity_monitoring = bool
enable_secure_boot = bool
enable_vtpm = bool
})
{
"enable_integrity_monitoring": true,
"enable_secure_boot": true,
"enable_vtpm": true
}
no
slurm_cluster_name Cluster name, used for resource naming and slurm accounting.
If not provided it will default to the first 8 characters of the deployment name (removing any invalid characters).
string null no
slurm_conf_tpl Slurm slurm.conf template file path. string null no
slurmdbd_conf_tpl Slurm slurmdbd.conf template file path. string null no
static_ips List of static IPs for VM instances. list(string) [] no
subnetwork_self_link Subnet to deploy to. string n/a yes
tags Network tag list. list(string) [] no
universe_domain Domain address for alternate API universe string "googleapis.com" no
zone Zone where the instances should be created. If not specified, instances will be
spread across available zones in the region.
string null no

Outputs

Name Description
instructions Post deployment instructions.
slurm_bucket_path Bucket path used by cluster.
slurm_cluster_name Slurm cluster name.
slurm_controller_instance Compute instance of controller node
slurm_login_instances Compute instances of login nodes