663c259ffa
Currently the codeparser cache ends up being extended for every parse run since there are values in the functions such as the result of os.getpid() from LOGFIFO in OE-Core. Digging into that issue, there are also lots of similar but different functions being parsed where the change might just be a path to WORKDIR, a change in PN or PV or something like DATE/TIME. There is no reason we have to use these changing values when computing the dependenies of the functions. Even with a small tweak like: BB_HASH_CODEPARSER_VALS = "LOGFIFO=/ T=/ WORKDIR=/ DATE=1234 TIME=1234 PV=0.0-1 PN=nopn" the cache is reduced from ~4.6MB, increasing by ~300kb for every parse run to around 1.3MB and remaining static for oe-core and meta-oe. In my local build, admittedly heavily experimented with, the cache had grown to 120MB. The benefits of doing this are: * faster load time for bitbake since the cache is smaller to read from disk and load into memory * being able to skip saving the cache upon shutdown * lower memory footprint for bitbake * faster codeparser data lookups (since there is less data to search) We only use these special values when passing code fragments to the codeparser to parse so the real variable values should otherwise be used in the hash data. The overall effect of this change, combined with others to avoid saving unchanged cache files can be ~2s on a ~16s parse on my local system and results in a more responsive feeling bitbake. It also allows parsing performance to be investigated more consistently. (Bitbake rev: f24bbaaddb36f479a59a958e7fc90ef454c19473) Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
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 https://www.openembedded.org/wiki/How_to_submit_a_patch_to_OpenEmbedded for guidelines on how to submit patches, just note that the latter documentation is intended for OpenEmbedded (and its core) not bitbake patches (bitbake-devel@lists.openembedded.org) but in general main guidelines apply. Once the commit(s) have been created, the way to send the patch is through git-send-email. For example, to send the last commit (HEAD) on current branch, type:
git send-email -M -1 --to bitbake-devel@lists.openembedded.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. Git must be correctly configured, in particular the user.email and user.name values must be set.
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