247e73e85a
This converts the virtual handling in the new concretizer from
already-ground rules to facts. This is the last thing that needs to be
refactored, and it converts the entire concretizer to just use facts.
The previous way of handling virtuals hinged on rules involving
`single_provider_for` facts that were tied to the virtual and a version
range. The new method uses the condition pattern we've been using for
dependencies, externals, and conflicts.
To handle virtuals as conditions, we impose constraints on "fake" virtual
specs in the logic program. i.e., `version_satisfies("mpi", "2.0:",
"2.0")` is legal whereas before we wouldn't have seen something like
this. Currently, constriants are only handled on versions -- we don't
handle variants or anything else yet, but they key change here is that we
*could*. For a long time, virtual handling in Spack has only dealt with
versions, and we'd like to be able to handle variants as well. We could
easily add an integrity constraint to handle variants like the one we use
for versions.
One issue with the implementation here is that virtual packages don't
actually declare possible versions like regular packages do. To get
around that, we implement an integrity constraint like this:
:- virtual_node(Virtual),
version_satisfies(Virtual, V1), version_satisfies(Virtual, V2),
not version_constraint_satisfies(Virtual, V1, V2).
This requires us to compare every version constraint to every other, both
in program generation and within the concretizer -- so there's a
potentially quadratic evaluation time on virtual constraints because we
don't have a real version to "anchor" things to. We just say that all the
constraints need to agree for the virtual constraint to hold.
We can investigate adding synthetic versions for virtuals in the future,
to speed this up.
|
||
|---|---|---|
| .github | ||
| bin | ||
| etc/spack/defaults | ||
| lib/spack | ||
| share/spack | ||
| var/spack | ||
| .codecov.yml | ||
| .coveragerc | ||
| .dockerignore | ||
| .flake8 | ||
| .flake8_packages | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .readthedocs.yml | ||
| CHANGELOG.md | ||
| COPYRIGHT | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| NOTICE | ||
| pytest.ini | ||
| README.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 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.
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, click here.
- 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