From 4ab132a20d33e70cf6736737c59d2c0ce2f79298 Mon Sep 17 00:00:00 2001 From: Scott Rifenbark Date: Mon, 19 Jan 2015 14:14:19 -0800 Subject: 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 (From yocto-docs rev: 3a27b1792c92a2f22173315e2732f672cdad2c78) Signed-off-by: Scott Rifenbark Signed-off-by: Richard Purdie --- documentation/dev-manual/dev-manual-start.xml | 7 +++-- documentation/ref-manual/closer-look.xml | 15 +++++------ documentation/ref-manual/ref-structure.xml | 8 ++---- documentation/ref-manual/ref-variables.xml | 23 +++++++---------- .../yocto-project-qs/yocto-project-qs.xml | 30 +++++++++------------- 5 files changed, 33 insertions(+), 50 deletions(-) (limited to 'documentation') diff --git a/documentation/dev-manual/dev-manual-start.xml b/documentation/dev-manual/dev-manual-start.xml index df29302fdb..c3206b86f8 100644 --- a/documentation/dev-manual/dev-manual-start.xml +++ b/documentation/dev-manual/dev-manual-start.xml @@ -297,10 +297,9 @@ This file defines many aspects of the build environment including the target machine architecture through the MACHINE variable, - the development machine's processor use through the - BB_NUMBER_THREADS and - PARALLEL_MAKE variables, and - a centralized tarball download directory through the + the packaging format used during the build + (PACKAGE_CLASSES), + and a centralized tarball download directory through the DL_DIR variable. Build the image using the bitbake command. diff --git a/documentation/ref-manual/closer-look.xml b/documentation/ref-manual/closer-look.xml index c0c0d619a4..eaf07d665f 100644 --- a/documentation/ref-manual/closer-look.xml +++ b/documentation/ref-manual/closer-look.xml @@ -162,9 +162,10 @@ Parallelism Options: Controlled by the - BB_NUMBER_THREADS + BB_NUMBER_THREADS, + PARALLEL_MAKE, and - PARALLEL_MAKE + BB_NUMBER_PARSE_THREADS variables. Target Machine Selection: Controlled by the @@ -216,12 +217,10 @@ For example, suppose you had several build environments and they shared some common features. You can set these default build properties here. - A good example is perhaps the level of parallelism you want - to use through the - BB_NUMBER_THREADS - and - PARALLEL_MAKE - variables. + A good example is perhaps the packaging format to use + through the + PACKAGE_CLASSES + variable. One useful scenario for using the conf/site.conf file is to extend your BBPATH diff --git a/documentation/ref-manual/ref-structure.xml b/documentation/ref-manual/ref-structure.xml index 14419d3a84..1098006c73 100644 --- a/documentation/ref-manual/ref-structure.xml +++ b/documentation/ref-manual/ref-structure.xml @@ -467,12 +467,8 @@ MACHINE for which you want to build, which package types you wish to use (PACKAGE_CLASSES), - the location from which you want to access downloaded files - (DL_DIR), - and how you want your host machine to use resources - (BB_NUMBER_THREADS - and - PARALLEL_MAKE). + and the location from which you want to access downloaded files + (DL_DIR). diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml index 7abad0460a..281c4e3e2d 100644 --- a/documentation/ref-manual/ref-variables.xml +++ b/documentation/ref-manual/ref-variables.xml @@ -729,20 +729,17 @@ BB_NUMBER_THREADS - BB_NUMBER_THREADS[doc] = "The maximum number of tasks BitBake should run in parallel at any one time. A good rule of thumb is for this variable to be twice the number of cores." + BB_NUMBER_THREADS[doc] = "The maximum number of tasks BitBake should run in parallel at any one time. This variable is automatically configured to be equal to the number of build system cores." The maximum number of tasks BitBake should run in parallel at any one time. - If your host development system supports multiple cores, - a good rule of thumb is to have this variable be twice the - number of cores. - - - - The default value for BB_NUMBER_THREADS - is equal to the number of cores your build system has. + The OpenEmbedded build system automatically configures + this variable to be equal to the number of cores on the + build system. + To gain optimal parallelism, you should not have to + override this variable. @@ -7380,11 +7377,9 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3" - If your development host supports multiple cores, a good - rule of thumb is to set this variable to twice the number - of cores on the host. - If you do not set PARALLEL_MAKE, it - defaults to the number of cores your build system has. + The OpenEmbedded build system automatically sets this + variable to be equal to the number of cores the build + system uses. Individual recipes might clear out this variable if the software being built has problems running its 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 @@ - Another couple of variables of interest are the - BB_NUMBER_THREADS and the - PARALLEL_MAKE variables. - By default, these variables are set to the number of processor - cores your build host uses. - However, if your build host uses multiple processor cores, - you should increase these settings to twice the number of - cores used. - Doing so can significantly shorten your build time. + Another three variables of interest are the + BB_NUMBER_THREADS, + PARALLEL_MAKE, + and + BB_NUMBER_PARSE_THREADS + variables. + By default, these variables are optimally set based on the + number of processor cores your build host uses. + Although it is possible to override these variables, the + default values the OpenEmbedded build system derives provide you + with parallelism during the build. @@ -898,18 +900,10 @@ conf/local.conf configuration file in the Build Directory. You need to manually edit this file to specify the machine you - are building and to optimize your build time. - Here are the minimal changes to make: + are building: - BB_NUMBER_THREADS = "8" - PARALLEL_MAKE = "-j 8" MACHINE ?= "beaglebone" - Briefly, set - BB_NUMBER_THREADS - and - PARALLEL_MAKE to - twice your host processor's number of cores. -- cgit v1.2.3-54-g00ecf