From mboxrd@z Thu Jan 1 00:00:00 1970 From: glebn@voltaire.com (Gleb Natapov) Subject: Re: [ofa-general] Re: [patch 5/6] mmu_notifier: Support for drivers with revers maps (f.e. for XPmem) Date: Tue, 26 Feb 2008 11:38:09 +0200 Message-ID: <20080226093809.GF26611@minantech.com> References: <20080215064859.384203497@sgi.com> <200802261711.33213.nickpiggin@yahoo.com.au> <20080226072137.GD26611@minantech.com> <200802261952.42567.nickpiggin@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andrea Arcangeli , Peter Zijlstra , Izik Eidus , Kanoj Sarcar , Roland Dreier , steiner@sgi.com, linux-kernel@vger.kernel.org, Avi Kivity , linux-mm@kvack.org, daniel.blueman@quadrics.com, Robin Holt , general@lists.openfabrics.org, akpm@linux-foundation.org, Christoph Lameter , kvm-devel@lists.sourceforge.net To: Nick Piggin Return-path: Content-Disposition: inline In-Reply-To: <200802261952.42567.nickpiggin@yahoo.com.au> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: general-bounces@lists.openfabrics.org Errors-To: general-bounces@lists.openfabrics.org List-Id: kvm.vger.kernel.org On Tue, Feb 26, 2008 at 07:52:41PM +1100, Nick Piggin wrote: > On Tuesday 26 February 2008 18:21, Gleb Natapov wrote: > > On Tue, Feb 26, 2008 at 05:11:32PM +1100, Nick Piggin wrote: > > > > You are missing one point here. The MPI specifications that have > > > > been out there for decades do not require the process use a library > > > > for allocating the buffer. I realize that is a horrible shortcoming, > > > > but that is the world we live in. Even if we could change that spec, > > > > > > Can you change the spec? > > > > Not really. It will break all existing codes. > > I meant as in eg. submit changes to MPI-3 MPI spec tries to be backward compatible. And MPI-2 spec is 10 years old, but MPI-1 is still in a wider use. HPC is moving fast in terms of HW technology, but slow in terms of SW. Fortran is still hot there :) -- Gleb.