There have been complaints about the performance of large multiconfig builds for a while. The key missing data point was that the builds needed to have large overlaps in sstate objects. This can be simulated by building the same things with just different TMPDIRs. In runqueue/bitbake terms this equates to large numbers of deferred tasks. The issue is that the expensive checks in the setscene loop were hit every time through runqueue's execute function before the check on deferred tasks. This leads to task execution starvation as that only happens once per iteration. Move the skip check earlier in the function which speeds things up enormously and should improve performance of such builds for users. (Bitbake rev: db083cfe9e33c9fd7ffeead7b8c6023a5d581976) Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org> (cherry picked from commit 9c6c506757f2b3e28c8b20513b45da6b4659c95f) Signed-off-by: Steve Sakoman <steve@sakoman.com>
Bitbake
BitBake is a generic task execution engine that allows shell and Python tasks to be run efficiently and in parallel while working within complex inter-task dependency constraints. One of BitBake's main users, OpenEmbedded, takes this core and builds embedded Linux software stacks using a task-oriented approach.
For information about Bitbake, see the OpenEmbedded website: https://www.openembedded.org/
Bitbake plain documentation can be found under the doc directory or its integrated html version at the Yocto Project website: https://docs.yoctoproject.org
Bitbake requires Python version 3.8 or newer.
Contributing
Please refer to our contributor guide here: https://docs.yoctoproject.org/contributor-guide/ for full details on how to submit changes.
As a quick guide, patches should be sent to bitbake-devel@lists.openembedded.org The git command to do that would be:
git send-email -M -1 --to bitbake-devel@lists.openembedded.org
If you're sending a patch related to the BitBake manual, make sure you copy the Yocto Project documentation mailing list:
git send-email -M -1 --to bitbake-devel@lists.openembedded.org --cc docs@lists.yoctoproject.org
Mailing list:
https://lists.openembedded.org/g/bitbake-devel
Source code:
https://git.openembedded.org/bitbake/
Testing
Bitbake has a testsuite located in lib/bb/tests/ whichs aim to try and prevent regressions. You can run this with "bitbake-selftest". In particular the fetcher is well covered since it has so many corner cases. The datastore has many tests too. Testing with the testsuite is recommended before submitting patches, particularly to the fetcher and datastore. We also appreciate new test cases and may require them for more obscure issues.
To run the tests "zstd" and "git" must be installed.
The assumption is made that this testsuite is run from an initialized OpenEmbedded build
environment (i.e. source oe-init-build-env is used). If this is not the case, run the
testsuite as follows:
export PATH=$(pwd)/bin:$PATH
bin/bitbake-selftest
The testsuite can alternatively be executed using pytest, e.g. obtained from PyPI (in this case, the PATH is configured automatically):
pytest