On Sat, 25 Aug 2007, Andi Kleen wrote:
> On Fri, Aug 24, 2007 at 05:50:18PM -0700, Siddha, Suresh B wrote:
> > On Fri, Aug 24, 2007 at 03:26:54PM -0700, [email protected] wrote:
> > > Previous Intro:
> >
> > Thanks for doing this.
> >
> > > In x86_64 and i386 architectures most arrays that are sized
> > > using NR_CPUS lay in local memory on node 0. Not only will most
> > > (99%?) of the systems not use all the slots in these arrays,
> > > particularly when NR_CPUS is increased to accommodate future
> > > very high cpu count systems, but a number of cache lines are
> > > passed unnecessarily on the system bus when these arrays are
> > > referenced by cpus on other nodes.
> >
> > Can we move cpuinfo_x86 also to per cpu area? Though critical run
>
> I worry how much impact that would be? boot_cpu_data is quite
> widely used.
>
I looked at this and it would be a big memory savings. But I haven't
yet analyzed the various accesses to verify that we can cleanly move
the structure, and that we don't suffer a bunch of tlb misses because
accesses are primarily from node 0.
More info soon.
Thanks,
Mike
-
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/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
