3 navsection: installguide
4 title: Singularity container runtime
7 Copyright (C) The Arvados Authors. All rights reserved.
9 SPDX-License-Identifier: CC-BY-SA-3.0
12 Arvados can be configured to use Singularity instead of Docker to execute containers on cloud nodes or a SLURM/LSF cluster.
15 * *Singularity support is currently considered experimental.*
16 * Even when using the singularity runtime, users' container images are expected to be saved in Docker format using @arv keep docker@. Arvados converts the Docker image to Singularity format (@.sif@) at runtime as needed. Specifying a @.sif@ file as an image when submitting a container request is not yet supported.
17 * Singularity does not limit the amount of memory available in a container. Each container will have access to all memory on the host where it runs.
18 * Programs running in containers may behave differently due to differences between Singularity and Docker, _e.g._, the root (image) filesystem is read-only in a Singularity container.
19 * Arvados is currently tested with Singularity version 3.5.2.
21 To use singularity, first make sure Singularity is installed on your cloud worker image or SLURM/LSF compute nodes as applicable.
24 <pre><code>$ <span class="userinput">singularity version</span>
29 Then update @Containers.RuntimeEngine@ in your cluster configuration:
32 <pre><code> # Container runtime: "docker" (default) or "singularity" (experimental)
33 RuntimeEngine: singularity
37 Restart your dispatcher (@crunch-dispatch-slurm@ or @arvados-dispatch-cloud@) after updating your configuration file.