ae6e83b1d5
Spack's `system` and `user` scopes provide ways for administrators and
users to set global defaults for all Spack instances, but for use cases
where one wants a clean Spack installation, these scopes can be undesirable.
For example, users may want to opt out of global system configuration, or
they may want to ignore their own home directory settings when running in
a continuous integration environment.
Spack also, by default, keeps various caches and user data in `~/.spack`,
but users may want to override these locations.
Spack provides three environment variables that allow you to override or
opt out of configuration locations:
* `SPACK_USER_CONFIG_PATH`: Override the path to use for the
`user` (`~/.spack`) scope.
* `SPACK_SYSTEM_CONFIG_PATH`: Override the path to use for the
`system` (`/etc/spack`) scope.
* `SPACK_DISABLE_LOCAL_CONFIG`: set this environment variable to completely
disable *both* the system and user configuration directories. Spack will
only consider its own defaults and `site` configuration locations.
And one that allows you to move the default cache location:
* `SPACK_USER_CACHE_PATH`: Override the default path to use for user data
(misc_cache, tests, reports, etc.)
With these settings, if you want to isolate Spack in a CI environment, you can do this:
export SPACK_DISABLE_LOCAL_CONFIG=true
export SPACK_USER_CACHE_PATH=/tmp/spack
This is a stop-gap approach until we have figured out how to deal with
the system and user config scopes more generally, as there are plans to
potentially / eventually get rid of them.
**User config**
Spack is a bit of a pain when you have:
- a shared $HOME folder across different systems.
- multiple Spack versions on the same system.
**System config**
- On shared systems with a versioned programming environment / toolkit,
system administrators want to provide config for each version (e.g.
21.09, 21.10) of the programming environment, and the user Spack
instance should be able to pick this up without a steep learning
curve.
- On shared systems the user should be able to opt out of the
hard-coded config scope in /etc/spack, since it may be incompatible
with their particular instance. Currently Spack can only opt out of all
config scopes through overrides with `"config:":`, `"packages:":`, but that
also drops the defaults config, which would have to be repeated, which
is undesirable, especially the lengthy packages.yaml.
An example use case is: having config in this folder:
```
/path/to/programming/environment/{version}/{compilers,packages}.yaml
```
and have `module load spack-system-config` set the variable
```
SPACK_SYSTEM_CONFIG_PATH=/path/to/programming/environment/{version}
```
where the user no longer has to worry about what `{version}` they are
on.
**Continuous integration**
Finally, there is the use case of continuous integration, which may
clone an arbitrary Spack version, which optimally should not pick up
system or user config from the previous run (like may happen in
classical bare metal non-containerized filesystem side effect ridden
jenkins pipelines). In fact this is very similar to how spack itself
tries to avoid picking up system dependencies during builds...
**But environments solve this?**
- You could do `include`s in environment files to get similar behavior
to the spack_system_config_path example, but environments require you
to:
1) require paths to individual config files, not directories.
2) fail if the listed config file does not exist
- They allow you to override config scopes, but this is generally too
rigurous, as it requires you to repeat the default config, in
particular packages.yaml, and just defies the point of layered config.
Co-authored-by: Tom Scogland <tscogland@llnl.gov>
Co-authored-by: Tim Fuller <tjfulle@sandia.gov>
Co-authored-by: Steve Leak <sleak@lbl.gov>
Co-authored-by: Todd Gamblin <tgamblin@llnl.gov>
|
||
|---|---|---|
| .github | ||
| bin | ||
| etc/spack/defaults | ||
| lib/spack | ||
| share/spack | ||
| var/spack | ||
| .codecov.yml | ||
| .dockerignore | ||
| .flake8 | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .readthedocs.yml | ||
| CHANGELOG.md | ||
| COPYRIGHT | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| NOTICE | ||
| pyproject.toml | ||
| pytest.ini | ||
| README.md | ||
| SECURITY.md | ||
Spack
Spack is a multi-platform package manager that builds and installs multiple versions and configurations of software. It works on Linux, macOS, and many supercomputers. Spack is non-destructive: installing a new version of a package does not break existing installations, so many configurations of the same package can coexist.
Spack offers a simple "spec" syntax that allows users to specify versions and configuration options. Package files are written in pure Python, and specs allow package authors to write a single script for many different builds of the same package. With Spack, you can build your software all the ways you want to.
See the Feature Overview for examples and highlights.
To install spack and your first package, make sure you have Python. Then:
$ git clone -c feature.manyFiles=true https://github.com/spack/spack.git
$ cd spack/bin
$ ./spack install zlib
Documentation
Full documentation is available, or
run spack help or spack help --all.
For a cheat sheet on Spack syntax, run spack help --spec.
Tutorial
We maintain a hands-on tutorial. It covers basic to advanced usage, packaging, developer features, and large HPC deployments. You can do all of the exercises on your own laptop using a Docker container.
Feel free to use these materials to teach users at your organization about Spack.
Community
Spack is an open source project. Questions, discussion, and contributions are welcome. Contributions can be anything from new packages to bugfixes, documentation, or even new core features.
Resources:
- Slack workspace: spackpm.slack.com. To get an invitation, visit slack.spack.io.
- Mailing list: groups.google.com/d/forum/spack
- Twitter: @spackpm. Be sure to
@mentionus!
Contributing
Contributing to Spack is relatively easy. Just send us a
pull request.
When you send your request, make develop the destination branch on the
Spack repository.
Your PR must pass Spack's unit tests and documentation tests, and must be PEP 8 compliant. We enforce these guidelines with our CI process. To run these tests locally, and for helpful tips on git, see our Contribution Guide.
Spack's develop branch has the latest contributions. Pull requests
should target develop, and users who want the latest package versions,
features, etc. can use develop.
Releases
For multi-user site deployments or other use cases that need very stable software installations, we recommend using Spack's stable releases.
Each Spack release series also has a corresponding branch, e.g.
releases/v0.14 has 0.14.x versions of Spack, and releases/v0.13 has
0.13.x versions. We backport important bug fixes to these branches but
we do not advance the package versions or make other changes that would
change the way Spack concretizes dependencies within a release branch.
So, you can base your Spack deployment on a release branch and git pull
to get fixes, without the package churn that comes with develop.
The latest release is always available with the releases/latest tag.
See the docs on releases for more details.
Code of Conduct
Please note that Spack has a Code of Conduct. By participating in the Spack community, you agree to abide by its rules.
Authors
Many thanks go to Spack's contributors.
Spack was created by Todd Gamblin, tgamblin@llnl.gov.
Citing Spack
If you are referencing Spack in a publication, please cite the following paper:
- Todd Gamblin, Matthew P. LeGendre, Michael R. Collette, Gregory L. Lee, Adam Moody, Bronis R. de Supinski, and W. Scott Futral. The Spack Package Manager: Bringing Order to HPC Software Chaos. In Supercomputing 2015 (SC’15), Austin, Texas, November 15-20 2015. LLNL-CONF-669890.
License
Spack is distributed under the terms of both the MIT license and the Apache License (Version 2.0). Users may choose either license, at their option.
All new contributions must be made under both the MIT and Apache-2.0 licenses.
See LICENSE-MIT, LICENSE-APACHE, COPYRIGHT, and NOTICE for details.
SPDX-License-Identifier: (Apache-2.0 OR MIT)
LLNL-CODE-811652