Default NR_CPUS==8 is not enough to cover high-end desktop configuration: Haswell-E has upto 16 threads.
Let's increase default NR_CPUS to 64 on 64-bit configuration. With this value CPU bitmask will still fit into one unsinged long. Default for 32-bit configuration is still 8: it's unlikely anybody will run 32-bit kernel on modern hardware. As alternative we could bump NR_CPUS to 128 to cover all dual-processor servers with some margin. For reference: Debian and Suse build their kernels with NR_CPUS==512, Fedora -- 1024. Signed-off-by: Kirill A. Shutemov <[email protected]> --- arch/x86/Kconfig | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6aaf38ac417d..c3333e5be5d7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -851,7 +851,8 @@ config NR_CPUS default "1" if !SMP default "8192" if MAXSMP default "32" if SMP && X86_BIGSMP - default "8" if SMP + default "8" if SMP && X86_32 + default "64" if SMP ---help--- This allows you to specify the maximum number of CPUs which this kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/

