forked from OSchip/llvm-project
30881272e1
Running lit tests and unit tests of ASan and TSan on macOS has very bad performance when running with a high number of threads. This is caused by xnu (the macOS kernel), which currently doesn't handle mapping and unmapping of sanitizer shadow regions (reserved VM which are several terabytes large) very well. The situation is so bad that increasing the number of threads actually makes the total testing time larger. The macOS buildbots are affected by this. Note that we can't easily limit the number of sanitizer testing threads without affecting the rest of the tests. This patch adds a special "group" into lit, and limits the number of concurrently running tests in this group. This helps solve the contention problem, while still allowing other tests to run in full, that means running lit with -j8 will still with 8 threads, and parallelism is only limited in sanitizer tests. Differential Revision: https://reviews.llvm.org/D28420 llvm-svn: 292548 |
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| .. | ||
| examples | ||
| lit | ||
| tests | ||
| utils | ||
| MANIFEST.in | ||
| README.txt | ||
| lit.py | ||
| setup.py | ||
README.txt
===============================
lit - A Software Testing Tool
===============================
lit is a portable tool for executing LLVM and Clang style test suites,
summarizing their results, and providing indication of failures. lit is designed
to be a lightweight testing tool with as simple a user interface as possible.
=====================
Contributing to lit
=====================
Please browse the Test Suite > lit category in LLVM's Bugzilla for ideas on
what to work on.
Before submitting patches, run the test suite to ensure nothing has regressed:
# From within your LLVM source directory.
utils/lit/lit.py \
--path /path/to/your/llvm/build/bin \
utils/lit/tests
Note that lit's tests depend on 'not' and 'FileCheck', LLVM utilities.
You will need to have built LLVM tools in order to run lit's test suite
successfully.
You'll also want to confirm that lit continues to work when testing LLVM.
Follow the instructions in http://llvm.org/docs/TestingGuide.html to run the
regression test suite:
make check-llvm
And be sure to run the llvm-lit wrapper script as well:
/path/to/your/llvm/build/bin/llvm-lit utils/lit/tests
Finally, make sure lit works when installed via setuptools:
python utils/lit/setup.py install
lit --path /path/to/your/llvm/build/bin utils/lit/tests