documentation: BB_NUMBER_THREADS and PARALLEL_MAKE suggestions

Text that suggests setting the BB_NUMBER_THREADS and
PARALLEL_MAKE variables to speed build time has been updated to
suggest a setting of twice the number of host cores supported.

The 2x number came to light through a discussion on the project
mailing list initiated by Robert P. J. Day.

Reported-by: Robert P. J. Day
(From yocto-docs rev: 1846b41a595b7bd905ca828eaa04112d1533d7a1)

Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 1 insertions, 4 deletions

diff --git a/documentation/yocto-project-qs/yocto-project-qs.xml b/documentation/yocto-project-qs/yocto-project-qs.xml
index fcbf3a1847..23e097b20f 100644
--- a/documentation/yocto-project-qs/yocto-project-qs.xml
+++ b/documentation/yocto-project-qs/yocto-project-qs.xml
@@ -410,11 +410,8 @@
              <ulink url='http://www.yoctoproject.org/docs/latest/poky-ref-manual/poky-ref-manual.html#var-PARALLEL_MAKE'><filename>PARALLEL_MAKE</filename></ulink> variables.
              By default, these variables are commented out. 
              However, if you have a multi-core CPU you might want to uncomment
-             the lines and set the variable
-             <filename>BB_NUMBER_THREADS</filename> equal to twice the number of your 
+             the lines and set both variables equal to twice the number of your 
              host's processor cores.
-             Also, you could set the variable <filename>PARALLEL_MAKE</filename> equal to 
-             1.5 times the number of processor cores.
              Setting these variables can significantly shorten your build time.
          </para>