From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: [PATCH v1 1/4] xen: add real time scheduler rt Date: Wed, 3 Sep 2014 16:35:50 +0200 Message-ID: <1409754950.2673.53.camel@Solace.lan> References: <1408921125-21470-1-git-send-email-mengxu@cis.upenn.edu> <1408921125-21470-2-git-send-email-mengxu@cis.upenn.edu> <53FCB571020000780002DAB7@mail.emea.novell.com> <53FD963B020000780002DED0@mail.emea.novell.com> <53FE0FA7020000780002E224@mail.emea.novell.com> <54005E82020000780002EFB1@mail.emea.novell.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============6668701459883197779==" 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: Meng Xu Cc: Ian Campbell , Sisu Xi , Stefano Stabellini , George Dunlap , Chenyang Lu , Ian Jackson , "xen-devel@lists.xen.org" , Linh Thi Xuan Phan , Meng Xu , Jan Beulich , Chao Wang , Chong Li , Dagaen Golomb List-Id: xen-devel@lists.xenproject.org --===============6668701459883197779== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-dOf9tYWyD7g90HvmYbg7" --=-dOf9tYWyD7g90HvmYbg7 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On mer, 2014-09-03 at 10:24 -0400, Meng Xu wrote: > 2014-09-03 10:08 GMT-04:00 George Dunlap > : > Under what circumstances would anyone want a period of an > hour? > =E2=80=8B =E2=80=8B > At > this point we're talking about a vcpu being allowed to run > continuously without pre-emption for half an hour, and then > not > *allowed* to run at all for another half hour. That just > seems really > ridiculous. >=20 >=20 > =E2=80=8BHonestly speaking, I don't think setting period and budget to ho= urs > is a good idea > =E2=80=8B either. =E2=80=8B > =20 Indeed, it makes no sense to me too. > How about this: > I change the type to uint32 bit and use 2^32us ~=3D 1.19h as the upper > bound of period and budget.=20 > Fine for me. > =E2=80=8BI document the range of period and budget on the website and als= o let > users know how to scale down the parameters of vcpus in case they have > a very large period and budget. >=20 I guess something like that won't harm on any website (BTW, are you talking about RT-Xen website? Xen Wiki? Both? :-D). In the code, I won't "waste" to much line of comments on this. I don't see any special need for explaining the scaling down either, it's pretty straightforward once you have even a very light knowledge of what the scheduling algorithm does (like the bare minimum you need for being able to use it!). Just make sure that you specify, especially in public headers of all the various components (so Xen, libxc and libxl) what the time unit is, that is _the_ important piece of information one needs to use the scheduler properly. Regards, Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-dOf9tYWyD7g90HvmYbg7 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 v2 iEYEABECAAYFAlQHJ0YACgkQk4XaBE3IOsQExQCfTUX4deY4Uv1r/Sg8Fd6AaSdc +WAAnA7CuW2FFfEBjOr4Njh9LTBDeyu1 =gy3d -----END PGP SIGNATURE----- --=-dOf9tYWyD7g90HvmYbg7-- --===============6668701459883197779== 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 --===============6668701459883197779==--