If you run devtool modify on the kernel (worst case example, but other recipes are affected) there are things being done that shouldn't be done - e.g. multiple parses of the configuration, summary messages, events etc. Here's the output where you can see some of it: ------------ snip ------------ $ devtool modify virtual/kernel Loading cache: 100% |########################################| Time: 0:00:00 Loaded 2181 entries from dependency cache. NOTE: Mapping virtual/kernel to linux-intel Loading cache: 100% |########################################| Time: 0:00:00 Loaded 2181 entries from dependency cache. NOTE: Executing RunQueue Tasks NOTE: Executing do_fetch... NOTE: Executing do_unpack... NOTE: Tasks Summary: Attempted 2 tasks of which 0 didn't need to be rerun and all succeeded. NOTE: Writing buildhistory NOTE: Executing RunQueue Tasks NOTE: Executing do_kernel_checkout... NOTE: Tasks Summary: Attempted 3 tasks of which 2 didn't need to be rerun and all succeeded. NOTE: Writing buildhistory NOTE: Patching... NOTE: Executing RunQueue Tasks NOTE: Executing do_validate_branches... NOTE: Executing do_kernel_metadata... NOTE: Executing do_patch... NOTE: Tasks Summary: Attempted 6 tasks of which 3 didn't need to be rerun and all succeeded. NOTE: Writing buildhistory NOTE: Generating kernel config NOTE: Executing RunQueue Tasks NOTE: Executing do_prepare_recipe_sysroot... NOTE: Executing do_kernel_configme... NOTE: Executing do_configure... NOTE: Tasks Summary: Attempted 9 tasks of which 6 didn't need to be rerun and all succeeded. NOTE: Writing buildhistory NOTE: Adding local source files to srctree... NOTE: Copying kernel config to srctree NOTE: Source tree extracted to /home/paul/poky/poky/build/workspace/sources/linux-intel NOTE: Recipe linux-intel now set up to build from /home/paul/poky/poky/build/workspace/sources/linux-intel ------------ snip ------------ We should try to tidy up the output and optimise the performance from the tinfoil side of things as much as possible.
So this is now fixed with the following changes (and probably some others): http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=a9848fdd46f4f567444e00892a0f5868deea1643 http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=7eb654cb4d82b54e3e4df0a57face61063b72c45 http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=192b2e15369fd052e5e4d5f70c5f5d83d50c2b5b Running devtool modify on the kernel still takes quite a long time but it's now mostly about the kernel tasks themselves rather than how they are being run.