How many cores does the ARM branch support?

Gregory CLEMENT gregory.clement at
Tue Oct 2 03:42:19 EDT 2012

On 10/02/2012 06:31 AM, Michelle Konzack wrote:
> Hello OverGeeks and *,

Hello Michelle,

> I have gotten a new gadget which run only with 700MHz but has  32 cores. Support 16 GE Interfaces a 50 Gbit universal interface and 4 PCIe ports, SATA HDD and much more...
> ...and yes, this ARM microcontroller is a telecommunications controller.
> However, I have the Evaluation  Kit  and  a  PCIe  graphiccard  and  now installed Debian ARMEL.  Unfortunately I get only 2 cores working...
> What must I do to get the other 30 cores?

You have to check that your kernel was compiled with CONFIG_NR_CPUS = 32.
Checks also that you don't have "nr_cpus=2" in your kernel parameter.

> (without them, my Marvel Discovery MV78200 us 5 times faster)
> And is it possibel, to get 100 cores running? (this is the bigger version of the microcontroller I have)

Currently the maximum number of core supported is limited to 32.
the NR_CPUS range is from 2 to 32 for ARM.


Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.

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