Messages in this thread | | | Date | Wed, 26 Mar 2008 22:23:12 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH] x86_64: resize NR_IRQS for large machines (re-submit) |
| |
* Alan Mayer <ajm@sgi.com> wrote:
> On machines with very large numbers of cpus, tables that are > dimensioned by NR_IRQS get very large, especially the irq_desc table. > They are also very sparsely used. When the cpu count is > > MAX_IO_APICS, use MAX_IO_APICS to set NR_IRQS, otherwise use NR_CPUS.
thanks Alan, applied this in place of the other patch.
this bit is still ugly:
> -#define NR_IRQS (NR_VECTORS + (32 *NR_CPUS)) > +#if NR_CPUS < MAX_IO_APICS > +#define NR_IRQS (NR_VECTORS + (32 * NR_CPUS)) > +#else > +#define NR_IRQS (NR_VECTORS + (32 * MAX_IO_APICS)) > +#endif > #define NR_IRQ_VECTORS NR_IRQS
but it doesnt really depart from the current status quo of huge [NR_IRQS] arrays either. Patches that make NR_IRQS a variable are welcome :)
Ingo
| |