Re: [PATCH 0/6] x86: Reduce Memory Usage and Inter-Node message traffic (v2)

From: Siddha, Suresh B
Date: Fri Aug 24 2007 - 20:50:29 EST


On Fri, Aug 24, 2007 at 03:26:54PM -0700, travis@xxxxxxx 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
time code doesn't access this area, it will be nice to move the cpuinfo_x86
also into per cpu area.

Perhaps the current cpuinfo_x86 layout might cause confusion and make people
add arch specific per cpu elements into cpuinfo_x86(thinking that it uses per
cpu area).

Wonder if this confusion is the reason for git commit f3fa8ebc

thanks,
suresh
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/