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Robert Yang
871fcd2c15
This can improve the performance a lot for "bitbake <recipe-native/cross/crosssdk>
-ccleansstate" when there are a lot of sstate files.
For example:
* Before
$ bitbake quilt-native -ccleansstate
- Check log.do_cleansstate:
Removing /sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_package.tgz*
Removing /sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_package_qa.tgz*
Removing /sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_package_write_rpm.tgz*
Removing /sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_packagedata.tgz*
Removing /sstate-cache/*/sstate:quilt-native::0.65:r0::3:*_populate_lic.tgz*
Removing /sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_populate_sysroot.tgz*
There are no package tasks for quilt-native, so the first 4 lines doesn't
make any sense, but the glob pattern "sstate-cache/*/*" is very time
consuming when there are no disk caches. E.g., I have more than 600,000
sstate files:
- Without disk caches
# echo 3 >/proc/sys/vm/drop_caches
$ time python3 -c 'import glob; glob.glob("/sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_package.tgz*")'
real 4m32.583s
user 0m5.768s
sys 0m12.892s
- With disk caches (e.g., run it in the second time)
$ time python3 -c 'import glob; glob.glob("/sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_package.tgz*")'
real 0m5.128s
user 0m2.772s
sys 0m2.308s
So the 4 removing *package* commands cost more than 20s or 272s in theory.
* After
$ bitbake quilt-native -ccleansstate
- Check log.do_cleansstate:
Removing /sstate-cache/*/sstate:quilt-native::0.65:r0::3:*_populate_lic.tgz*
Removing /sstate-cache/*/*/sstate:quilt-native:x86_64-linux:0.65:r0:x86_64:3:*_populate_sysroot.tgz*
We can see that it saved 20s or 272s in theory.
(From OE-Core rev: bb2d6349ea87f090c58001f0d4348b24c2982cde)
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
QEMU Emulation Targets ====================== To simplify development, the build system supports building images to work with the QEMU emulator in system emulation mode. Several architectures are currently supported in 32 and 64 bit variants: * ARM (qemuarm + qemuarm64) * x86 (qemux86 + qemux86-64) * PowerPC (qemuppc only) * MIPS (qemumips + qemumips64) Use of the QEMU images is covered in the Yocto Project Reference Manual. The appropriate MACHINE variable value corresponding to the target is given in brackets.