On Mon, 2009-02-16 at 17:46 +1030, Rusty Russell wrote: > On Saturday 14 February 2009 10:18:05 Peter Zijlstra wrote: > > On Sat, 2009-02-14 at 07:46 +1030, Rusty Russell wrote: > > > I'd be fascinated to see perf numbers once you kill the kmalloc. Because > > > this patch will add num_possible_cpus * NR_CPUS/8 bytes to the kernel which > > > is something we're trying to avoid unless necessary. > > > > You're free to make it a pointer and do node affine allocations from an > > init section of choice and add a hotplug handler. > > > > But I'm not quite sure how perf is affected by size overhead on > > ridiculous configs. > > No, I meant "can you actually measure the perf win of this patch?". If you > did so, I missed it? Over what, the always single-ipi case, or the kmalloc case? The thing is, we're removing that kmalloc because its somewhat of a wart on the whole thing. > But if this patch is worthwhile, the right way to do this is make it a > cpumask_var_t, and do the alloc_cpumask_var_node() in that init routine. Right, and installing a hotplug handler and ... *sigh* -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
