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Date: Wed, 09 Jan 2013 10:31:47 -0800
From: Saul Wold <sgw@linux.intel.com>
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To: "Robert P. J. Day" <rpjday@crashcourse.ca>
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Subject: Re: [PATCH] local.conf.sample: Suggest parallelism of twice the number of cores.
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On 01/09/2013 10:14 AM, Robert P. J. Day wrote:
>
> To be consistent with the Yocto Quick Start Guide, recommend that
> parallelism represent twice the number of cores on a multi-core
> machine.
>
> Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
>
> ---
>
> diff --git a/meta/conf/local.conf.sample b/meta/conf/local.conf.sample
> index 859eb93..46187ce 100644
> --- a/meta/conf/local.conf.sample
> +++ b/meta/conf/local.conf.sample
> @@ -24,9 +24,9 @@
>   #
>   #PARALLEL_MAKE = "-j 4"
>   #
> -# For a quad-core machine, BB_NUMBER_THREADS = "4", PARALLEL_MAKE = "-j 4" would
> -# be appropriate for example.
> -
> +# If you have a multi-core machine, you would normally set both of these variables
> +# to twice the number of cores.  So for a quad-core machine, it would be appropriate
> +# to set BB_NUMBER_THREADS = "8" and PARALLEL_MAKE = "-j 8".

I think adding a note to ensure that hyperthreading is enabled would be 
appropriate, then number of threads = number of hyperthreaded cores (4 
vs 8).

Sau!

>   #
>   # Machine Selection
>   #
>