GPU Access

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Interactive Jobs in the GPU partition are limited to 6 hrs

Normalized Graphics Processor Units (NGUs) include all of the infrastructure (memory, network, rack space, cooling) necessary for GPU-accelerated computation. Each NGU is equivalent to 1 GPU presently, however newer GPUs such as the A100s may require more than 1 NGU to access in the future.

Researchers can add NGUs to their allocations by filling out the Purchase Form or requesting a Trial Allocation.

GPU-enabled Services

Types of GPUs are listed below. Two partitions contain GPUs - the hwgui partition for visualization and the gpu partition for general computation.

Hardware Accelerated GUI

GPUs in these servers are used to accelerate rendering for graphical applications. These servers are in the SLURM "hwgui" partition. Refer to the Hardware Accelerated GUI Sessions page for more information on available resources and usage.

GPU Assisted Computation

A number of high performance applications installed on HiPerGator implement GPU-accelerated computing functions via CUDA to achieve significant speed-up over CPU calculations. These servers are in the SLURM "gpu" partition (--partition=gpu).

Hardware Specifications for the GPU Partition

We have the following types of NVIDIA GPU nodes available in the "gpu" partition:

GPU Host Quantity Host Architecture Host Memory Host Interconnect CPUs per Host CPUS per Socket GPUs per Host CPUs per GPU Memory per GPU SLURM Feature GRES GPU type
GeForce 1080Ti 1 Intel Haswell 128 GB FDR IB 28 14 2 14 11GB n/a geforce
GeForce 2080Ti 32 Intel Skylake 187 GB EDR IB 32 16 8 4 11GB 2080ti geforce
GeForce 2080Ti 38 Intel Cascade Lake 187 GB EDR IB 32 16 8 4 11GB 2080ti geforce
Quadro RTX 6000 6 Intel Cascade Lake 187 GB EDR IB 32 16 8 4 23GB rtx6000 quadro
NVIDIA A100 140 AMD EPYC ROME 2 TB HDR IB 256 16 8 32 80GB a100 tesla

For a list of additional node features, see the Available Node Features page.

To select a specific type of GPU within a partition please use either a SLURM constraint (e.g. --constraint=rtx6000) or a GRES with the needed GPU type (--gres or --gpu=tesla:1). See more examples below.

Compiling CUDA Enabled Programs

The most direct way to develop a custom GPU accelerated algorithm is with the CUDA programming, please refer to the Nvidia CUDA Toolkit page. The current CUDA environment is cuda/11. However, C++ or Python packages numba and PyCuda are other ways to program GPU algorithms.

Slurm and GPU Use

Policy

  • After purchase, NGU allocations are included in your groups resources (quality of service).
  • To increase the availability of GPU resources, the time limit for the gpu partition is 7-days (at most #SBATCH --time=7-00:00:00). If you have a workload requiring more time, please create a help request.

Interactive Access

In order to request interactive command line access to a GPU under SLURM, use commands similar to these:

  • To request access to one GPU (of any type) for a default 1 hour session:
srun -p gpu --gpus=1 --pty -u bash -i
  • To request access to two Tesla GPUs on a single node for a 3-hour session with 300gb RAM:
srun -p gpu --nodes=1 --gpus=tesla:2 --time=03:00:00 --mem=300gb  --pty -u bash -i
  • To request access to two GeForce GPUs with multiple CPUs:
srun -p gpu --nodes=1 --gpus=geforce:2 --time=01:00:00 --ntasks=1 --cpus-per-task=8 --mem 300gb  --pty -u bash -i

Interactive sessions are limited to 6 hours.

Open On Demand Access

To access GPUs using Open-On-Demand, please check the form for your application. If your application supports multiple GPU types, choose the GPU partition and specify number of GPUs and type:

  • To request access to one GPU (of any type, use this gres string):
gpu:1
  • To request multiple GPUs (of any type, use this gres string were n is the number of GPUs you need):
gpu:n
  • To request a specific type of GPU, use this gres string (requesting geforce GPUs in this example):
gpu:geforce:1

Batch Jobs

For batch jobs, to request GPU resources, use lines similar to the following:

  • In this example, two Tesla GPUs on a single server (--nodes defaults to "1") will be allocated to the job:
#SBATCH --partition=gpu
#SBATCH --gpus=tesla:2
  • In this example, two GeForce GPUs on a single server (--nodes defaults to "1") will be allocated to the job:
#SBATCH --partition=gpu
#SBATCH --gpus=geforce:2


Alternatively, use '--gres=gpu:1' or '--gres=gpu:geforce:1' format. Note, if '--gpus=' format is used SLURM will not provide the data on GPU usage to slurmInfo and those GPUs will not be shown in slurmInfo output.

If no GPUs are available, your request will be queued and your connection established once the next GPU becomes available. Otherwise, you may cancel your job and try lowering requested resources. If you have requested a longer time than is needed, please be sure to end your session so that the GPU will be available for other users.

SLURM Options for A100 GPUs

To use A100 GPUs for interactive sessions or batch jobs, please use one of the following SLURM parameters:

--partition=gpu
--gpus=tesla:2

Job Script Examples

MPI Parallel

This is a sample script for MPI parallel VASP job requesting and using GPUs under SLURM:

#!/bin/bash
#SBATCH --job-name=vasptest
#SBATCH --output=vasp.out
#SBATCH --error=vasp.err
#SBATCH --mail-type=ALL
#SBATCH --mail-user=email@ufl.edu
#SBATCH --nodes=1
#SBATCH --ntasks=8
#SBATCH --cpus-per-task=1
#SBATCH --ntasks-per-node=8
#SBATCH --ntasks-per-socket=4
#SBATCH --mem-per-cpu=7000mb
#SBATCH --distribution=cyclic:cyclic
#SBATCH --partition=gpu
#SBATCH --gres=gpu:geforce:4
#SBATCH --time=00:30:00

echo "Date      = $(date)"
echo "host      = $(hostname -s)"
echo "Directory = $(pwd)"

module purge
module load cuda/10.0.130  intel/2018  openmpi/4.0.0 vasp/5.4.4

T1=$(date +%s)
srun --mpi=pmix_v3 vasp_gpu
T2=$(date +%s)

ELAPSED=$((T2 - T1))
echo "Elapsed Time = $ELAPSED"