Mount whole directories into the sandbox when possible

This halves the overhead with sandboxing enabled vs disabled for a test
that basically only mounts a bunch of files out of a directory, and
slows that same test with a single extra file added to the directory
(but not mounted) by only ~4%.

The test is <https://gist.github.com/bsilver8192/10527a862ce16bb7f79a>
with 30000 inputs moved to a subdirectory and only 10 genrules.

This change means symlinks will be mounted directly as their target
rather than as a symlink, but this solves some weird behavior with
multi-level symlinks and will only break things which don't declare all
of their dependencies.

--
Change-Id: I1aa39dccb2e5fca2893bdab9065ee043d34019b2
Reviewed-on: https://bazel-review.googlesource.com/#/c/3220/
MOS_MIGRATED_REVID=119138157
3 files changed
tree: 3f97461ad3a6d59b57291c383fa32025414a96aa
  1. examples/
  2. scripts/
  3. site/
  4. src/
  5. third_party/
  6. tools/
  7. .gitattributes
  8. .gitignore
  9. AUTHORS
  10. BUILD
  11. CHANGELOG.md
  12. compile.sh
  13. CONTRIBUTING.md
  14. CONTRIBUTORS
  15. LICENSE.txt
  16. README.md
  17. WORKSPACE
README.md

Bazel (Beta)

{Fast, Correct} - Choose two

Bazel is a build tool that builds code quickly and reliably. It is used to build the majority of Google‘s software, and thus it has been designed to handle build problems present in Google’s development environment, including:

  • A massive, shared code repository, in which all software is built from source. Bazel has been built for speed, using both caching and parallelism to achieve this. Bazel is critical to Google's ability to continue to scale its software development practices as the company grows.

  • An emphasis on automated testing and releases. Bazel has been built for correctness and reproducibility, meaning that a build performed on a continuous build machine or in a release pipeline will generate bitwise-identical outputs to those generated on a developer's machine.

  • Language and platform diversity. Bazel's architecture is general enough to support many different programming languages within Google, and can be used to build both client and server software targeting multiple architectures from the same underlying codebase.

Find more background about Bazel in our FAQ.

Getting Started

About the Bazel project: