From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Jackson Date: Sun, 17 Jul 2005 03:50:38 +0000 Subject: Re: [NUMA] Display and modify the memory policy of a process Message-Id: <20050716205038.48c05e96.pj@sgi.com> List-Id: References: <20050715214700.GJ15783@wotan.suse.de> <20050715220753.GK15783@wotan.suse.de> <20050715223756.GL15783@wotan.suse.de> <20050715225635.GM15783@wotan.suse.de> <20050715234402.GN15783@wotan.suse.de> <20050716020141.GO15783@wotan.suse.de> <20050716163030.0147b6ba.pj@sgi.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Christoph Lameter Cc: ak@suse.de, kenneth.w.chen@intel.com, linux-mm@kvack.org, linux-ia64@vger.kernel.org Christoph wrote: > Correct. We could implement the changing of policies via an extension > of the existing libnuma. That could be easily done as far as I can > tell. If that is done then the patch that I proposed is no longer > necessary. But then libnuma needs to also be extended to > > 1. Allow the discovery of the memory policies of each vma for each > process I'm missing something here. Are you saying that just a change to libnuma would suffice to accomplish what you sought with this patch? If that's the case, we don't need a kernel patch, right? And despite Andi's urging us to only access these facilities via libnuma, there is no law to that affect that I know of. At the least, you could present user level only code that accomplished the object of this patch set, with no kernel change. I don't think that is possible, short of gross hackery on /dev/mem. I think some sort of kernel change is required to enable one task to change the numa policy of another task. What the heck, over ?? -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401