Re: [MM] Make mm counters per cpu instead of atomic

From: Christoph Lameter
Date: Thu Nov 05 2009 - 13:03:08 EST


On Thu, 5 Nov 2009, KAMEZAWA Hiroyuki wrote:

> Hmm, I don't fully understand _new_ percpu but...
> In logical (even if not realistic), x86-32 supports up to 512 ? cpus in Kconfig.
> BIGSMP.

x86-32 only supports 32 processors. Plus per cpu areas are only allocated
for the possible processors.

> Then, if 65536 process runs, this consumes
>
> 65536(nr_proc) * 8 (size) * 512(cpus) = 256MBytes.

With 32 possible cpus this results in 16m of per cpu space use.

--
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/