| Summary: | contradiction between docs and local.conf comments regarding parallelism options | ||
|---|---|---|---|
| Product: | [Documentation] Quick Start | Reporter: | Cristian Ciupitu <cristian.ciupitu> |
| Component: | quick-start | Assignee: | Scott Rifenbark <srifenbark> |
| Status: | RESOLVED FIXED | QA Contact: | |
| Severity: | janitors | ||
| Priority: | Low | CC: | poky.doc.watcher, poky.watcher, sgw |
| Version: | unspecified | ||
| Target Milestone: | 1.3 | ||
| Hardware: | x86 | ||
| OS: | Multiple | ||
| URL: | http://git.yoctoproject.org/cgit.cgi/yocto-docs/commit/?id=b6b820371cbe43e39425156c72c45df283fdf7d1 | ||
| Whiteboard: | 4 Oct 2012 - Resolved/Fixed | ||
| OS type for building Yocto: | --- | Type of Regression: | --- |
| Verified: | Documentation change: | --- | |
So I checked out all the areas in the YP manuals that discuss BB_NUMBER_THREADS and PARALLEL_MAKE. Every instance in the documents (except one in a note in the Appendix B of the YP Development Manual) suggests that both these variables be set to twice the number of processors the host machine has. This single instance where the note suggested that PARALLEL_MAKE be set at 1.5x times the number of processors is an inconsistency in the manual set. I fixed that inconsistency so that all suggest now 2x. However, the local.conf file (as noted) does indeed have a suggested example of setting these variables both at 1x. What needs to be changed is the commented example in the local.conf file. I am unsure of what base file is used to create the local.conf file when a user runs the environment setup script. I am guessing it is local.conf.sample (http://git.yoctoproject.org/cgit.cgi/poky/tree/meta-yocto/conf) inside meta-yocto/conf. I think this bug needs to be re-assigned to whoever maintains that file. The manuals are all in line now with a suggested 2x setting for both the variables. Scott I am marking this bug fixed because the YP documentation is consistent in how it advises the user to set both BB_NUMBER_THREADS and PARALLEL_MAKE. Every occurrence suggests 2x based on the number of cores on the development system. Because the bug is against the documentation it is fixed. I did comment below in Comment 1 that the local.conf file should be fixed to also say 2x and not 4 based on a quad-core machine. There should be a new bug opened against the local.conf file or someone should just fix it. Scott |
The "Configuring the local.conf File" section[1] says: Briefly, set BB_NUMBER_THREADS and PARALLEL_MAKE to twice your host processor's number of cores. So a quad-core machine should have them set to 8, but the local.conf from a poky denzil build says: # For a quad-core machine, BB_NUMBER_THREADS = "4", PARALLEL_MAKE = "-j 4" would # be appropriate for example. [1] http://www.yoctoproject.org/docs/current/yocto-project-qs/yocto-project-qs.html#configuring-the-local.conf-file