From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: NUMA TODO-list for xen-devel Date: Wed, 08 Aug 2012 01:49:54 +0200 Message-ID: <1344383394.1890.11.camel@Solace> References: <1343837796.4958.32.camel@Solace> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============3761522102143106158==" Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Dan Magenheimer Cc: Andre Przywara , Anil Madhavapeddy , George Dunlap , Andrew Cooper , Konrad Wilk , xen-devel , Jan Beulich , Kurt Hackel , "Zhang, Yang Z" List-Id: xen-devel@lists.xenproject.org --===============3761522102143106158== Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-wJDHyyRKEVT2RgpqoFvW" --=-wJDHyyRKEVT2RgpqoFvW Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2012-08-03 at 15:22 -0700, Dan Magenheimer wrote: > Hi Dario -- >=20 Hello Dan, > Thanks for your great work on NUMA... an interest area of > mine but one, sadly, I haven't been able to give much time to, > so I'm glad you've taken this bull by the horns. >=20 Trying to... Let's see! :-P > I've been sitting on an idea for some time that probably > deserves some exposure on your list. Naturally, it involves > my favorite topic tmem (readers, please don't tune out yet :-). >=20 It sure does! I've already put something quite generic about "memory sharing" there, because I know that it has all but trivial interactions with the improved NUMA support I am/we are trying to envision. The fact that it is, as I said, generic, is due to my ignorance (let's say for now) of the whole tmem thing, so thanks for the contribution, it's very useful to hear your point of view on this! > It has occurred to me that a fundamental tenet of NUMA > is to put infrequently used data on "other" nodes, while > pulling frequently used data onto a "local" node. >=20 > Tmem very nicely separates infrequently-used data from > frequently-used data with an API/ABI that is now fully > implemented in upstream Linux. >=20 I see, and it seems nice. > [..] > > Naturally, this doesn't solve any NUMA problems at all for > tmem-ignorant or tmem-disabled guests, but if it works > sufficiently well for tmem-enabled guests, that might > encourage other OS's to do a simple implementation of tmem. >=20 Sure. In my opinion, this is not an area where we could aim at "solving every problem for everyone". However, we should definitely target having a sensible solution for default and/or most common use cases and scenarios. > Sadly, I'm not able to invest much time in this idea, > but the combination of tmem and NUMA might interest some > developers and/or grad students, in which case I'd be happy > to spend a little time assisting. >=20 That's definitely the case. I've tried to put a summary of what you said in this mail to the Wiki (http://wiki.xen.org/wiki/Xen_NUMA_Roadmap) and also put your contact next to it. Feel free to update/correct if you fin something wrong. :-P > I'll be at Xen Summit for at least the first day, so we > can chat more if you are interested. > I indeed am interested, so let's make that happen! :-) Thanks and Regards, Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://retis.sssup.it/people/faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-wJDHyyRKEVT2RgpqoFvW Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEABECAAYFAlAhqaIACgkQk4XaBE3IOsSQZACdEfjV77miGGTfawJzIL+yI0Cl 18gAmwSvtv6TFpEtt2v4kA0O/gPlAOs+ =jeiU -----END PGP SIGNATURE----- --=-wJDHyyRKEVT2RgpqoFvW-- --===============3761522102143106158== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel --===============3761522102143106158==--