Re: [RFC PATCH 0/5] Refcount based Cpu Hotplug. V2

From: Christoph Lameter
Date: Wed Oct 24 2007 - 13:05:57 EST


On Wed, 24 Oct 2007, Gautham R Shenoy wrote:

> This is the version 2 of the refcount based cpu-hotplug "locking"
> implementation.

Uggh. This introduces a global lock that has to be taken always when
scanning over cpus? Is multipe cpus are scanning over processor lists then
we will get into scaling problems. Wasnt there an RCU based implementation
that avoided cacheline bouncing and refcounting?

> The patchstack which is based against 2.6.23-mm1 has behaved well
> when it was stress tested with kernbench running while continuously
> performing cpu-hotplug operations on i386, x86_64 and ppc64.

What was the highest cpu count in testing?
-
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/