{Singularity} natively supports running application containers that use NVIDIA's CUDA GPU compute framework, or AMD's ROCm solution. This allows easy access to users of GPU-enabled machine learning frameworks such as tensorflow, regardless of the host operating system. As long as the host has a driver and library installation for CUDA/ROCm then it's possible to e.g. run tensorflow in an up-to-date Ubuntu 20.04 container, from an older RHEL 7 host.
Applications that support OpenCL for compute acceleration can also be used easily, with an additional bind option.
With {Singularity} 3.9 experimental support has been introduced to use
NVIDIA's nvidia-container-cli
tooling for GPU container setup. This
functionality, accessible via the new --nvccli
flag, improves
compatibility with OCI runtimes and exposes additional container
configuration options.
Commands that run
, or otherwise execute containers (shell
,
exec
) can take an --nv
option, which will setup the container's
environment to use an NVIDIA GPU and the basic CUDA libraries to run a
CUDA enabled application. The --nv
flag will:
- Ensure that the
/dev/nvidiaX
device entries are available inside the container, so that the GPU cards in the host are accessible. - Locate and bind the basic CUDA libraries from the host into the container, so that they are available to the container, and match the kernel GPU driver on the host.
- Set the
LD_LIBRARY_PATH
inside the container so that the bound-in version of the CUDA libraries are used by applications run inside the container.
To use the --nv
flag to run a CUDA application inside a container
you must ensure that:
- The host has a working installation of the NVIDIA GPU driver, and a matching version of the basic NVIDIA/CUDA libraries. The host does not need to have an X server running, unless you want to run graphical apps from the container.
- The NVIDIA libraries are in the system's library search path.
- The application inside your container was compiled for a CUDA version, and device capability level, that is supported by the host card and driver.
These requirements are usually satisfied by installing the NVIDIA drivers and CUDA packages directly from the NVIDIA website. Linux distributions may provide NVIDIA drivers and CUDA libraries, but they are often outdated which can lead to problems running applications compiled for the latest versions of CUDA.
{Singularity} will find the NVIDIA/CUDA libraries on your host using the
list of libraries in the configuration file
etc/singularity/nvbliblist
, and resolving paths through the
ldconfig
cache. At time of release this list is appropriate for the
latest stable CUDA version. It can be modified by the administrator to
add additional libraries if necessary. See the admin guide for more
details.
Tensorflow is commonly used for machine learning projects but can be difficult to install on older systems, and is updated frequently. Running tensorflow from a container removes installation problems and makes trying out new versions easy.
The official tensorflow repository on Docker Hub contains NVIDA GPU supporting containers, that will use CUDA for processing. You can view the available versions on the tags page on Docker Hub
The container is large, so it's best to build or pull the docker image to a SIF before you start working with it:
$ singularity pull docker://tensorflow/tensorflow:latest-gpu ... INFO: Creating SIF file... INFO: Build complete: tensorflow_latest-gpu.sif
Then run the container with GPU support:
$ singularity run --nv tensorflow_latest-gpu.sif ________ _______________ ___ __/__________________________________ ____/__ /________ __ __ / _ _ \_ __ \_ ___/ __ \_ ___/_ /_ __ /_ __ \_ | /| / / _ / / __/ / / /(__ )/ /_/ / / _ __/ _ / / /_/ /_ |/ |/ / /_/ \___//_/ /_//____/ \____//_/ /_/ /_/ \____/____/|__/ You are running this container as user with ID 1000 and group 1000, which should map to the ID and group for your user on the Docker host. Great! Singularity>
You can verify the GPU is available within the container by using the
tensorflow list_local_devices()
function:
Singularity> python Python 2.7.15+ (default, Jul 9 2019, 16:51:35) [GCC 7.4.0] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> from tensorflow.python.client import device_lib >>> print(device_lib.list_local_devices()) 2019-11-14 15:32:09.743600: I tensorflow/core/platform/cpu_feature_guard.cc:142] Your CPU supports instructions that this TensorFlow binary was not compiled to use: AVX2 FMA 2019-11-14 15:32:09.784482: I tensorflow/core/platform/profile_utils/cpu_utils.cc:94] CPU Frequency: 3292620000 Hz 2019-11-14 15:32:09.787911: I tensorflow/compiler/xla/service/service.cc:168] XLA service 0x565246634360 executing computations on platform Host. Devices: 2019-11-14 15:32:09.787939: I tensorflow/compiler/xla/service/service.cc:175] StreamExecutor device (0): Host, Default Version 2019-11-14 15:32:09.798428: I tensorflow/stream_executor/platform/default/dso_loader.cc:44] Successfully opened dynamic library libcuda.so.1 2019-11-14 15:32:09.842683: I tensorflow/stream_executor/cuda/cuda_gpu_executor.cc:1006] successful NUMA node read from SysFS had negative value (-1), but there must be at least one NUMA node, so returning NUMA node zero 2019-11-14 15:32:09.843252: I tensorflow/compiler/xla/service/service.cc:168] XLA service 0x5652469263d0 executing computations on platform CUDA. Devices: 2019-11-14 15:32:09.843265: I tensorflow/compiler/xla/service/service.cc:175] StreamExecutor device (0): GeForce GT 730, Compute Capability 3.5 2019-11-14 15:32:09.843380: I tensorflow/stream_executor/cuda/cuda_gpu_executor.cc:1006] successful NUMA node read from SysFS had negative value (-1), but there must be at least one NUMA node, so returning NUMA node zero 2019-11-14 15:32:09.843984: I tensorflow/core/common_runtime/gpu/gpu_device.cc:1618] Found device 0 with properties: name: GeForce GT 730 major: 3 minor: 5 memoryClockRate(GHz): 0.9015 ...
By default, {Singularity} makes all host devices available in the
container. When the --contain
option is used a minimal /dev
tree
is created in the container, but the --nv
option will ensure that
all nvidia devices on the host are present in the container.
This behaviour is different to nvidia-docker
where an
NVIDIA_VISIBLE_DEVICES
environment variable is used to control
whether some or all host GPUs are visible inside a container. The
nvidia-container-runtime
explicitly binds the devices into the
container dependent on the value of NVIDIA_VISIBLE_DEVICES
.
To control which GPUs are used in a {Singularity} container that is run
with --nv
you can set SINGULARITYENV_CUDA_VISIBLE_DEVICES
before
running the container, or CUDA_VISIBLE_DEVICES
inside the container.
This variable will limit the GPU devices that CUDA programs see.
E.g. to run the tensorflow container, but using only the first GPU in the host, we could do:
$ SINGULARITYENV_CUDA_VISIBLE_DEVICES=0 singularity run --nv tensorflow_latest-gpu.sif # or $ export SINGULARITYENV_CUDA_VISIBLE_DEVICES=0 $ singularity run tensorflow_latest-gpu.sif
If the host installation of the NVIDIA / CUDA driver and libraries is working and up-to-date there are rarely issues running CUDA programs inside of {Singularity} containers. The most common issue seen is:
CUDA depends on multiple kernel modules being loaded. Not all of the modules are loaded at system startup. Some portions of the NVIDA driver stack are initialized when first needed. This is done using a setuid root binary, so initializing can be triggered by any user on the host. In {Singularity} containers, privilege escalation is blocked, so the setuid root binary cannot initialize the driver stack fully.
If you experience CUDA_ERROR_UNKNOWN
in a container, initialize the
driver stack on the host first, by running a CUDA program there or
modprobe nvidia_uvm
as root, and using nvidia-persistenced
to
avoid driver unload.
{Singularity} 3.9 introduces the --nvccli
option, which will
instruct {Singularity} to perform GPU container setup using the
nvidia-container-cli
utility. This utility must be installed
separately from {Singularity}. It is available in the repositories of
some distributions, and at:
https://nvidia.github.io/libnvidia-container/
Warning
This feature is considered experimental in {Singularity} 3.9. It cannot not replace the legacy NVIDIA support in all situations, and should be tested carefully before use in production workflows.
Using nvidia-container-cli
to configure a container for GPU
operation has a number of advantages, including:
- The tool is maintained by NVIDIA, and will track new features / libraries in new CUDA releases closely.
- Support for passing only specific GPUs / MIG devices into the container.
- Support for providing different classes of GPU capability to the container, e.g. compute, graphics, and display functionality.
- Configuration via the same environment variables that are in use with OCI containers.
nvidia-container-cli
must be installed on your host, owned by theroot
user. Its path must be set insingularity.conf
. This value will be set at build time ifnvidia-container-cli
is found on the search$PATH
.- Your system should support the
overlay
filesystem if you will be running SIF containers in set-uid mode. --nvccli
cannot currently be used in combination with--fakeroot
in a set-uid install of Singularity. Use the traditional binding method with--nv
only.- There are known problems with library discovery for the current
nvidia-container-cli
in recent Debian distributions. See this GitHub issue
Tensorflow can be run using --nvccli
in the same manner as the
legacy --nv
binding approach. Pull the large container to a SIF
file:
$ singularity pull docker://tensorflow/tensorflow:latest-gpu ... INFO: Creating SIF file... INFO: Build complete: tensorflow_latest-gpu.sif
Then run the container with nvidia-container-cli
GPU support:
$ singularity run --nv --nvccli tensorflow_latest-gpu.sif INFO: Setting --writable-tmpfs (required by nvidia-container-cli) ________ _______________ ___ __/__________________________________ ____/__ /________ __ __ / _ _ \_ __ \_ ___/ __ \_ ___/_ /_ __ /_ __ \_ | /| / / _ / / __/ / / /(__ )/ /_/ / / _ __/ _ / / /_/ /_ |/ |/ / /_/ \___//_/ /_//____/ \____//_/ /_/ /_/ \____/____/|__/ You are running this container as user with ID 1000 and group 1000, which should map to the ID and group for your user on the Docker host. Great! Singularity>
Note that --writable--tmpfs
was automatically set, which allows
files to be written inside the container to an ephemeral overlay that
will be discarded on exit. This is required for the
nvidia-container-cli
functionality.
You can verify the GPU is available within the container by using the
tensorflow list_local_devices()
function:
Singularity> python Python 2.7.15+ (default, Jul 9 2019, 16:51:35) [GCC 7.4.0] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> from tensorflow.python.client import device_lib >>> print(device_lib.list_local_devices()) ... device_type: "GPU" memory_limit: 14474280960 locality { bus_id: 1 links { } } incarnation: 13349913758992036690 physical_device_desc: "device: 0, name: Tesla T4, pci bus id: 0000:00:1e.0, compute capability: 7.5" ...
When running with --nvccli
, by default {Singularity} will expose all
GPUs on the host inside the container. This mirrors the functionality of
the legacy GPU support for the most common use-case.
Setting the SINGULARITY_CUDA_VISIBLE_DEVICES
environment variable
before running a container is still supported, to control which GPUs are
used by CUDA programs that honor CUDA_VISIBLE_DEVICES
. However, more
powerful GPU isolation is possible using the --contain
flag and
NVIDIA_VISIBLE_DEVICES
environment variable. This controls which GPU
devices are bound into the /dev
tree in the container.
For example, to pass only the 2nd and 3rd GPU into a container running on a system with 4 GPUs, run the following:
$ export NVIDIA_VISIBLE_DEVICES=1,2 $ singularity run --contain --nv --nvccli mycontainer.sif
Note that:
NVIDIA_VISIBLE_DEVICES
is not prepended withSINGULARITY_
as this variable controls container setup, and is not passed into the container.- The GPU device identifiers start at 0, so 1,2 refers to the 2nd and 3rd GPU.
- You can use GPU UUIDs in place of numeric identifiers. Use
nvidia-smi -L
to list both numeric IDs and UUIDs available on the system. all
can be used to pass all available GPUs into the container.
If you use --contain
without setting NVIDIA_VISIBLE_DEVICES
, no
GPUs will be available in the container, and a warning will be shown:
$ singularity run --contain --nv --nvccli mycontainer.sif WARNING: When using nvidia-container-cli with --contain NVIDIA_VISIBLE_DEVICES must be set or no GPUs will be available in container.
To restore the behaviour of the legacy GPU handling, set
NVIDIA_VISIBLE_DEVICES=0
when running with --contain
.
If your system contains Ampere or newer GPUs that support virtual MIG devices, you can specify MIG identifiers / UUIDs.
$ export NVIDIA_VISIBLE_DEVICES=MIG-GPU-5c89852c-d268-c3f3-1b07-005d5ae1dc3f/7/0
{Singularity} does not configure MIG partitions. It is expected that these would be statically configured by the system administrator, or setup dynamically by a job scheduler / workflow system according to the requirements of the job.
In --nvccli
mode, {Singularity} understands the following additional
environment variables. Note that these environment variables are read
from the environment where singularity
is run. {Singularity} does
not currently read these settings from the container environment.
NVIDIA_DRIVER_CAPABILITIES
controls which libraries and utilities are mounted in the container, to support different requirements. The default value under {Singularity} iscompute,utility
, which will provide CUDA functionality and basic utilities such asnvidia-smi
. Other options includegraphics
for OpenGL/Vulkan support,video
for the codecs SDK, anddisplay
to use X11 from a container.NVIDIA_REQUIRE_*
variables allow specifying requirements, which will be checked bynvidia-container-cli
prior to starting the container. Constraints can be set oncuda
,driver
,arch
, andbrand
values. Docker/OCI images may set these variables inside the container, to indicate runtime requirements. However, these container variables are not yet interpreted by {Singularity}.NVIDIA_DISABLE_REQUIRE
will disable the enforcement of anyNVIDIA_REQUIRE_*
requirements that are set.
Full details of the supported values for these environment variables can be found in the container-toolkit guide:
{Singularity} 3.5 adds a --rocm
flag to support GPU compute with the
ROCm framework using AMD Radeon GPU cards.
Commands that run
, or otherwise execute containers (shell
,
exec
) can take an --rocm
option, which will setup the
container's environment to use a Radeon GPU and the basic ROCm libraries
to run a ROCm enabled application. The --rocm
flag will:
- Ensure that the
/dev/dri/
device entries are available inside the container, so that the GPU cards in the host are accessible. - Locate and bind the basic ROCm libraries from the host into the container, so that they are available to the container, and match the kernel GPU driver on the host.
- Set the
LD_LIBRARY_PATH
inside the container so that the bound-in version of the ROCm libraries are used by application run inside the container.
To use the --rocm
flag to run a CUDA application inside a container
you must ensure that:
- The host has a working installation of the
amdgpu
driver, and a compatible version of the basic ROCm libraries. The host does not need to have an X server running, unless you want to run graphical apps from the container. - The ROCm libraries are in the system's library search path.
- The application inside your container was compiled for a ROCm version that is compatible with the ROCm version on your host.
These requirements can be satisfied by following the requirements on the ROCm web site
Tensorflow is commonly used for machine learning projects, but can be difficult to install on older systems, and is updated frequently. Running tensorflow from a container removes installation problems and makes trying out new versions easy.
The rocm tensorflow repository on Docker Hub contains Radeon GPU supporting containers, that will use ROCm for processing. You can view the available versions on the tags page on Docker Hub
The container is large, so it's best to build or pull the docker image to a SIF before you start working with it:
$ singularity pull docker://rocm/tensorflow:latest ... INFO: Creating SIF file... INFO: Build complete: tensorflow_latest.sif
Then run the container with GPU support:
$ singularity run --rocm tensorflow_latest.sif
You can verify the GPU is available within the container by using the
tensorflow list_local_devices()
function:
Singularity> ipython Python 3.5.2 (default, Jul 10 2019, 11:58:48) Type 'copyright', 'credits' or 'license' for more information IPython 7.8.0 -- An enhanced Interactive Python. Type '?' for help. >>> from tensorflow.python.client import device_lib ... >>> print(device_lib.list_local_devices()) ... 2019-11-14 16:33:42.750509: I tensorflow/core/common_runtime/gpu/gpu_device.cc:1651] Found device 0 with properties: name: Lexa PRO [Radeon RX 550/550X] AMDGPU ISA: gfx803 memoryClockRate (GHz) 1.183 pciBusID 0000:09:00.0 ...
Both the --rocm
and --nv
flags will bind the vendor OpenCL
implementation libraries into a container that is being run. However,
these libraries will not be used by OpenCL applications unless a vendor
icd file is available under /etc/OpenCL/vendors
that directs OpenCL
to use the vendor library.
The simplest way to use OpenCL in a container is to --bind
/etc/OpenCL
so that the icd files from the host (which match the
bound-in libraries) are present in the container.
The Sylabs examples repository contains an example container definition for the 3D modelling application 'Blender'.
The latest versions of Blender supports OpenCL rendering. You can run Blender as a graphical application that will make use of a local Radeon GPU for OpenCL compute using the container that has been published to the Sylabs library:
$ singularity exec --rocm --bind /etc/OpenCL library://sylabs/examples/blender blender
Note the exec used as the runscript for this container is setup for batch rendering (which can also use OpenCL).