052b2e1b08
This converts everything in cc to POSIX sh, except for the parts currently
handled with bash arrays. Tests are still passing.
This version tries to be as straightforward as possible. Specifically, most conversions
are kept simple -- convert ifs to ifs, handle indirect expansion the way we do in
`setup-env.sh`, only mess with the logic in `cc`, and don't mess with the python code at
all.
The big refactor is for arrays. We can't rely on bash's nice arrays and be ignorant of
separators anymore. So:
1. To avoid complicated separator logic, there are three types of lists. They are:
* `$lsep`-separated lists, which end with `_list`. `lsep` is customizable, but we
picked `^G` (alarm bell) for `$lsep` because it's ASCII and it's unlikely that it
would actually appear in any arguments. If we need to get fancier (and I will lose
faith in the world if we do) then we could consider XON or XOFF.
* `:`-separated directory lists, which end with `_dirs`, `_DIRS`, `PATH`, or `PATHS`
* Whitespace-separated lists (like flags), which can have any other name.
Whitespace and colon-separated lists come with the territory with PATHs from env
vars and lists of flags. `^G` separated lists are what we use for most internal
variables, b/c it's more likely to work.
2. To avoid subshells, use a bunch of functions that do dirty `eval` stuff instead. This
adds 3 functions to deal with lists:
* `append LISTNAME ELEMENT [SEP]` will put `ELEMENT` at the end of the list called
`LISTNAME`. You can optionally say what separator you expect to use. Note that we
are taking advantage of everything being global and passing lists by name.
* `prepend LISTNAME ELEMENT [SEP]` like append, but puts `ELEMENT` at the start of
`LISTNAME`
* `extend LISTNAME1 LISTNAME2 [PREFIX]` appends everything in LISTNAME2 to
LISTNAME1, and optionally prepends `PREFIX` to every element (this is useful for
things like `-I`, `-isystem `, etc.
* `preextend LISTNAME1 LISTNAME2 [PREFIX]` prepends everything in LISTNAME2 to
LISTNAME1 in order, and optionally prepends `PREFIX` to every element.
The routines determine the separator for each argument by its name, so we don't have to
pass around separators everywhere. Amazingly, as long as you do not expand variables'
values within an `eval` environment, you can do all this and still preserve quoting.
When iterating over lists, the user of this API still has to set and unset `IFS`
properly.
We ended up having to ignore shellcheck SC2034 (unused variable), because using evals
all over the place means that shellcheck doesn't notice that our list variables are
actually used.
So far this is looking pretty good. I took the most complex unit test I could find
(which runs a sample link line) and ran the same command line 200 times in a shell
script. Times are roughly as follows:
For this invocation:
```console
$ bash -c 'time (for i in `seq 1 200`; do ~/test_cc.sh > /dev/null; done)'
```
I get the following performance numbers (the listed shells are what I put in `cc`'s
shebang):
**Original**
* Old version of `cc` with arrays and `bash v3.2.57` (macOS builtin): `4.462s` (`.022s` / call)
* Old version of `cc` with arrays and `bash v5.1.8` (Homebrew): `3.267s` (`.016s` / call)
**Using many subshells (#26408)**
* with `bash v3.2.57`: `25.302s` (`.127s` / call)
* with `bash v5.1.8`: `27.801s` (`.139s` / call)
* with `dash`: `15.302s` (`.077s` / call)
This version didn't seem to work with zsh.
**This PR (no subshells)**
* with `bash v3.2.57`: `4.973s` (`.025s` / call)
* with `bash v5.1.8`: `4.984s` (`.025s` / call)
* with `zsh`: `2.995s` (`.015s` / call)
* with `dash`: `1.890s` (`.0095s` / call)
Dash, with the new posix design, is easily the winner.
So there are several interesting things to note here:
1. Running the posix version in `bash` is slower than using `bash` arrays. That is to be
expected because it's doing a bunch of string processing where it likely did not have
to before, at least in `bash`.
2. `zsh`, at least on macOS, is significantly faster than the ancient `bash` they ship
with the system. Using `zsh` with the new version also makes the posix wrappers
faster than `develop`. So it's worth preferring `zsh` if we have it. I suppose we
should also try this with newer `bash` on Linux.
3. `bash v5.1.8` seems to be significantly faster than the old system `bash v3.2.57` for
arrays. For straight POSIX stuff, it's a little slower. It did not seem to matter
whether `--posix` was used.
4. `dash` is way faster than `bash` or `zsh`, so the real payoff just comes from being
able to use it. I am not sure if that is mostly startup time, but it's significant.
`dash` is ~2.4x faster than the original `bash` with arrays.
So, doing a lot of string stuff is slower than arrays, but converting to posix seems
worth it to be able to exploit `dash`.
- [x] Convert all but array-related portions to sh
- [x] Fix basic shellcheck issues.
- [x] Convert arrays to use a few convenience functions: `append` and `extend`
- [x] Get `cc` tests passing.
- [x] Add `cc` tests where needed passing.
- [x] Benchmarking.
Co-authored-by: Tom Scogland <scogland1@llnl.gov>
Co-authored-by: Danny McClanahan <1305167+cosmicexplorer@users.noreply.github.com>
|
||
|---|---|---|
| .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