Alpine Hardware

Hardware Summary

Count & Type Scheduler Partition Processor Sockets Cores (total) Threads/Core RAM/Core (GB) L3 Cache (MB) GPU type GPU count Local Disk Capacity & Type Fabric OS
256 Milan General CPU amilan x86_64 AMD Milan 1 or 2 64 1 3.8 32 N/A 0 416G SSD HDR-100 InfiniBand (200Gb inter-node fabric) RHEL 8.4
12 Milan High-Memory amem x86_64 AMD Milan 2 48 1 21.5 tbd N/A 0 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4
8 Milan High-Memory amem x86_64 AMD Milan 1 64 1 16 tbd N/A 0 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4
8 Milan AMD GPU ami100 x86_64 AMD Milan 2 64 1 3.8 32 AMD MI100 3 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4
8 Milan NVIDIA GPU aa100 x86_64 AMD Milan 2 64 1 3.8 32 NVIDIA A100 3 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4
28 Milan General CPU csu x86_64 AMD Milan 2 48 1 3.8 32 N/A 0 416G SSD HDR-100 InfiniBand (200Gb inter-node fabric) RHEL 8.4
49 Milan General CPU csu x86_64 AMD Milan 2 32 1 3.8 32 N/A 0 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4
14 Milan General CPU amc x86_64 AMD Milan 2 64 1 3.8 32 NVIDIA A100 0 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4
2 Milan High-Memory amc,amem x86_64 AMD Milan 2 64 1 21.5 32 N/A 0 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4
4 Milan NVIDIA GPU amc x86_64 AMD Milan 2 64 1 3.8 32 N/A 3 416G SSD 2x25 Gb Ethernet +RoCE RHEL 8.4

Requesting Hardware Resources

Resources are requested within jobs by passing in SLURM directives, or resource flags, to either a job script (most common) or to the command line when submitting a job. Below are some common resource directives for Alpine (summarized then detailed):

  • Gres (General Resources): Specifies the number of GPUs (required if using a GPU node)
  • QOS (Quality of Service): Constrains or modifies job characteristics
  • Partition: Specifies node type

General Resources (gres)

General resources allows for fine-grain hardware specifications. On Alpine the gres directive is required to use GPU accelerators on GPU nodes. At a minimum, one would specify --gres=gpu in their job script (or on the command line when submitting a job) to specify that they would like to use a single gpu on their specified partition. One can also request multiple GPU accelerators on nodes that have multiple accelerators. Alpine GPU resources and configurations can be viewed as follows on a login node with the slurm/alpine module loaded:

$ sinfo --Format NodeList:30,Partition,Gres |grep gpu |grep -v "mi100|a100"

Examples of GPU configurations/requests:

request a single GPU accelerator:

--gres=gpu

request multiple (in this case 3) GPU accelerators:

--gres=gpu:3

Quality of Service (qos)

Quality of Service or QoS is used to constrain or modify the characteristics that a job can have. This could come in the form of specifying a QoS to request for a longer run time. For example, by selecting the long QoS, a user can place the job in a lower priority queue with a max wall time increased from 24 hours to 7 days.

The available QoS’s for Alpine are:

QOS name Description Max walltime Max jobs/user Node limits Partition limits Priority Adjustment
normal Default 1D 1000 128 amilan,aa100,ami100 0
long Longer wall times 7D 200 20 amilan,aa100,ami100 0
mem High-memory jobs 7D 1000 12 amem only 0

Partitions

Nodes with the same hardware configuration are grouped into partitions. You specify a partition using --partition SLURM directive in your job script (or at the command line when submitting an interactive job) in order for your job to run on the appropriate type of node.

Note: GPU nodes require the additional --gres directive (see above section).

Partitions available on Alpine:

Partition Description # of nodes cores/node RAM/core (GB) Billing_weight/core Default/Max Walltime Resource Limits
amilan AMD Milan (default) 347 32 or 48 or 64 3.75 1 24H, 24H see qos table
ami100 GPU-enabled (3x AMD MI100) 8 64 3.75 6.13 24H, 24H 15 GPUs across all jobs
aa100 GPU-enabled (3x NVIDIA A100)4 12 64 3.75 6.13 24H, 24H 22 GPUs across all jobs
amem1 High-memory 14 48 or 64 162 4.0 4H, 7D 96 cores across all jobs
csu Nodes contributed by CSU 77 32 or 48 3.75 1 24H, 24H see qos table

1The amem partition requires the mem QOS. The mem QOS is only available to jobs asking for 256GB of RAM or more, 12 nodes or fewer, and 96 cores or fewer. For example, you can run one 96-core job or up to two 48-core jobs, etc. If you need more memory or cores, please contact rc-help@colorado.edu.

2The amem partition has 12 nodes with 48 cores, and 10 nodes with 64 cores. All nodes have 1 TB of RAM. The default RAM-per-requested core on the amem partition is 15,927 MB, which is configured such that if you request all 64 cores on a 64-core amem node, you will receive roughly 1,000,000 MB of RAM (i.e., the full ~1 TB available). If you request all 48 cores on a 48-core node, by default you will receive 764,496 MB of RAM, which is less than the 1 TB available. If you require more RAM than the default of 15,927 MB per-requested-core, employ the --mem flag in your job script and specify the amount of RAM you need, in MB. For example, to request all of the RAM on a node, use “–mem=1000000M”.

3On the GPU partitions, aa100 and ami100, the billing_weight value of 6.1/core is an aggregate estimate. In practice, users are billed 1.0 for each core they request, and 108.2 for each GPU they request. For example, if a user requests all 64 cores and all three GPUs for one hour, they will be billed (1.0 * 64) + (108.2 * 3)=389 SUs.

4NVIDIA A100 GPUs only support CUDA versions >11.x

All users, regardless of institution, should specify partitions as follows:

--partition=amilan
--partition=aa100
--partition=ami100
--partition=amem
--partition=csu

Special-purpose partitions

atesting provides access to limited resources for the purpose of verifying workflows and MPI jobs. Users are able to request up to 2 CPU nodes (8 cores per node) for a maximum runtime of 3 hours (default 30 minutes) and 16 CPUs. Users who need GPU nodes to test workflows should use the appropriate GPU testing partitions (atesting_a100 or atesting_mi100) instead of atesting.

atesting usage examples:

Request one core per node for 10 minutes

sinteractive --partition=atesting --ntasks-per-node=1 --nodes=2 --time=00:10:00

Request 4 cores for the default time of 30 minutes

sinteractive --partition=atesting --ntasks=4  

Request 2 cores each from 2 nodes for testing MPI

sinteractive --ntasks-per-node=2 --nodes=2 --partition=atesting 

atesting_a100 and atesting_mi100 provide access to limited GPU resources for the purpose of verifying GPU workflows and building GPU-accelerated applications. Users can request up to 3 GPUs and all associated CPU cores (64 max) from a single node for up to one hour (default one hour).

Usage examples:

Request 2 A100 GPUs with 40 CPU cores for 30 minutes.

sinteractive --partition=atesting_a100 --gres=gpu:2 --ntasks=40 --time=30:00

Request 1 MI100 GPU with 1 CPU core for one hour.

sinteractive --partition=atesting_mi100 --gres=gpu:1 --ntasks=1 --time=60:00

acompile provides near-immediate access to limited resources for the purpose of viewing the module stack and compiling software. Users can request up to 4 CPU cores (but no GPUs) for a maximum runtime of 12 hours. The partition is accessed with the acompile command. Users who need GPU nodes to compile software should use Slurm’s sinteractive command with the appropriate GPU partition (ami100 or aa100) instead of acompile.

acompile usage examples:

Get usage information for acompile

acompile --help

Request 2 CPU cores for 2 hours

acompile --ntasks=2 --time=02:00:00

Alpine is jointly funded by the University of Colorado Boulder, the University of Colorado Anschutz, Colorado State University, and the National Science Foundation (award 2201538).