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author | Scott Rifenbark <scott.m.rifenbark@intel.com> | 2015-01-19 14:14:19 -0800 |
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committer | Richard Purdie <richard.purdie@linuxfoundation.org> | 2015-02-17 15:16:51 +0000 |
commit | 4ab132a20d33e70cf6736737c59d2c0ce2f79298 (patch) | |
tree | 5525f7940beb4783d345feea1ec86ec049d0bae1 /documentation/yocto-project-qs/yocto-project-qs.xml | |
parent | 0a367c514b86998f302da4e6d98fedaa8b4e8aaf (diff) | |
download | poky-4ab132a20d33e70cf6736737c59d2c0ce2f79298.tar.gz |
dev-manual, ref-manual, yocto-project-qs: Updates to parallelism variables
The way the old manual set had worded the use of the
BB_NUMBER_THREADS, PARALLEL_MAKE, and BB_NUMBER_PARSE_THREADS
had become depricated. It suggested a lot of user intervention
to get these variables set to have the build system utilize
optimal parallelism. The change a while back to the build system
where the variables are set to the number of build host cores
now makes the variables automatically be set to their best
values. I have gone through the manual set and changed wordings
appropriately to reflect this.
Reported-by: Robert P. J. Day <rpjday@crashcourse.ca>
(From yocto-docs rev: 3a27b1792c92a2f22173315e2732f672cdad2c78)
Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Diffstat (limited to 'documentation/yocto-project-qs/yocto-project-qs.xml')
-rw-r--r-- | documentation/yocto-project-qs/yocto-project-qs.xml | 30 |
1 files changed, 12 insertions, 18 deletions
diff --git a/documentation/yocto-project-qs/yocto-project-qs.xml b/documentation/yocto-project-qs/yocto-project-qs.xml index 8fe9b766e6..f21558ebbd 100644 --- a/documentation/yocto-project-qs/yocto-project-qs.xml +++ b/documentation/yocto-project-qs/yocto-project-qs.xml | |||
@@ -509,15 +509,17 @@ | |||
509 | </para> | 509 | </para> |
510 | 510 | ||
511 | <para> | 511 | <para> |
512 | Another couple of variables of interest are the | 512 | Another three variables of interest are the |
513 | <ulink url='&YOCTO_DOCS_REF_URL;#var-BB_NUMBER_THREADS'><filename>BB_NUMBER_THREADS</filename></ulink> and the | 513 | <ulink url='&YOCTO_DOCS_REF_URL;#var-BB_NUMBER_THREADS'><filename>BB_NUMBER_THREADS</filename></ulink>, |
514 | <ulink url='&YOCTO_DOCS_REF_URL;#var-PARALLEL_MAKE'><filename>PARALLEL_MAKE</filename></ulink> variables. | 514 | <ulink url='&YOCTO_DOCS_REF_URL;#var-PARALLEL_MAKE'><filename>PARALLEL_MAKE</filename></ulink>, |
515 | By default, these variables are set to the number of processor | 515 | and |
516 | cores your build host uses. | 516 | <ulink url='&YOCTO_DOCS_BB_URL;#var-BB_NUMBER_PARSE_THREADS'><filename>BB_NUMBER_PARSE_THREADS</filename></ulink> |
517 | However, if your build host uses multiple processor cores, | 517 | variables. |
518 | you should increase these settings to twice the number of | 518 | By default, these variables are optimally set based on the |
519 | cores used. | 519 | number of processor cores your build host uses. |
520 | Doing so can significantly shorten your build time. | 520 | Although it is possible to override these variables, the |
521 | default values the OpenEmbedded build system derives provide you | ||
522 | with parallelism during the build. | ||
521 | </para> | 523 | </para> |
522 | 524 | ||
523 | <para> | 525 | <para> |
@@ -898,18 +900,10 @@ | |||
898 | <filename>conf/local.conf</filename> configuration file | 900 | <filename>conf/local.conf</filename> configuration file |
899 | in the Build Directory. | 901 | in the Build Directory. |
900 | You need to manually edit this file to specify the machine you | 902 | You need to manually edit this file to specify the machine you |
901 | are building and to optimize your build time. | 903 | are building: |
902 | Here are the minimal changes to make: | ||
903 | <literallayout class='monospaced'> | 904 | <literallayout class='monospaced'> |
904 | BB_NUMBER_THREADS = "8" | ||
905 | PARALLEL_MAKE = "-j 8" | ||
906 | MACHINE ?= "beaglebone" | 905 | MACHINE ?= "beaglebone" |
907 | </literallayout> | 906 | </literallayout> |
908 | Briefly, set | ||
909 | <ulink url='&YOCTO_DOCS_REF_URL;#var-BB_NUMBER_THREADS'><filename>BB_NUMBER_THREADS</filename></ulink> | ||
910 | and | ||
911 | <ulink url='&YOCTO_DOCS_REF_URL;#var-PARALLEL_MAKE'><filename>PARALLEL_MAKE</filename></ulink> to | ||
912 | twice your host processor's number of cores. | ||
913 | </para> | 907 | </para> |
914 | 908 | ||
915 | <para> | 909 | <para> |