4c69970bd3
This unlikely looking function was found to be eating a lot of CPU time since it gets called once per trip through the idle loop if we're not running a maximum number of processes. This was particularly true in world builds of 13,000 tasks. Calling the computation code is pretty pointless because until some other task finishes nothing is going to become available to build. We can know when things become available so this patch teaches the scheduler this knowledge. It also: * skips any coputation when nothing can be built * if there is only one available item to build, ignore the priority map * precomputes the stamp filenames, rather than doing it every time * saves the length of the array rather than calculating it each time (the extra function overhead is significant) Timing wise, initially, 5000 iterations through here was 20s, with the patch 200000 calls takes the same time. The end result is that builds get up and running faster. (Bitbake rev: 4841c1d37c503a366f99e3a134dca7440e3a08ea) Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
Poky is an integration of various components to form a complete prepackaged build system and development environment. It features support for building customised embedded device style images. There are reference demo images featuring a X11/Matchbox/GTK themed UI called Sato. The system supports cross-architecture application development using QEMU emulation and a standalone toolchain and SDK with IDE integration.
Additional information on the specifics of hardware that Poky supports is available in README.hardware. Further hardware support can easily be added in the form of layers which extend the systems capabilities in a modular way.
As an integration layer Poky consists of several upstream projects such as BitBake, OpenEmbedded-Core, Yocto documentation and various sources of information e.g. for the hardware support. Poky is in turn a component of the Yocto Project.
The Yocto Project has extensive documentation about the system including a reference manual which can be found at: http://yoctoproject.org/documentation
OpenEmbedded-Core is a layer containing the core metadata for current versions of OpenEmbedded. It is distro-less (can build a functional image with DISTRO = "") and contains only emulated machine support.
For information about OpenEmbedded, see the OpenEmbedded website: http://www.openembedded.org/
Where to Send Patches
As Poky is an integration repository, patches against the various components should be sent to their respective upstreams.
bitbake: bitbake-devel@lists.openembedded.org
meta-yocto: poky@yoctoproject.org
Most everything else should be sent to the OpenEmbedded Core mailing list. If in doubt, check the oe-core git repository for the content you intend to modify. Before sending, be sure the patches apply cleanly to the current oe-core git repository. openembedded-core@lists.openembedded.org
Note: The scripts directory should be treated with extra care as it is a mix of oe-core and poky-specific files.