From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: [PATCH RFC v1] xen:rtds: towards work conserving RTDS Date: Mon, 7 Aug 2017 21:14:49 +0200 Message-ID: <1502133289.18446.8.camel@citrix.com> References: <1501611210-5232-1-git-send-email-mengxu@cis.upenn.edu> <1501695998.19956.10.camel@citrix.com> <1502127315.18446.6.camel@citrix.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============9116637548970594774==" Return-path: Received: from mail6.bemta6.messagelabs.com ([193.109.254.103]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1denUQ-0007kR-2h for xen-devel@lists.xenproject.org; Mon, 07 Aug 2017 19:14:58 +0000 In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" To: Meng Xu Cc: George Dunlap , "xen-devel@lists.xenproject.org" List-Id: xen-devel@lists.xenproject.org --===============9116637548970594774== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="=-Qz2OKbu2Dou4b5FuZ1ff" --=-Qz2OKbu2Dou4b5FuZ1ff Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2017-08-07 at 14:27 -0400, Meng Xu wrote: > On Mon, Aug 7, 2017 at 1:35 PM, Dario Faggioli >=20 > > Is this wanted or expected? >=20 > It is wanted. >=20 > A VCPU i that has already got budget_i * priority_level_i time has > higher priority than another VCPU j that got budget_j * > priority_level_j time, where priority_level_j > priority_level_i. >=20 > For the unreserved resource, a VCPU will gets roughly budget/period > proportional unreserved CPU time. >=20 >=20 > > Basically, if I'm not wrong, this means that the actual priority, > > during the extratime phase, is some combination of deadline and > > budget > > (which would make me think to utilization)... is this the case? >=20 > Yes. > The higher utilization a VCPU has, the more extra time it will get in > the extratime phase. >=20 > >=20 > > I don't care much about the actual schedule during the extratime > > phase, > > in the sense that it doesn't have to be anything too complicated or > > super advanced... but I at least would like: > > - to know how it works, and hence what to expect, > > - for it to be roughly fair. >=20 > The unreserved resource is proportionally allocated to VCPUs roughly > based on VCPU's budget/period. >=20 Right. Then this deserves both: - a quick mention in the changelog - a little bit more detailed explanation in a comment close to one of=C2=A0 the place where the policy is enacted (or at the top of the file,=C2=A0 or,=C2=A0well, somewhere :-) ) Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-Qz2OKbu2Dou4b5FuZ1ff 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 iQIcBAABCAAGBQJZiLwpAAoJEBZCeImluHPuWi8QANaSaUUe3wCna7a1n9/Fw6gl T5S6xiz1LHlw3rqpJcfFxR9a46wHSflPfZq3RCfBm3UGYffTdJYUf69zKmiDrD1D O7pbtNO6F2ROaYhK0b9KTiWiEfrbRW3RLoniJZPSZg8T7mRivy/VQH06RajJ2Sj5 t0UvdfhnAdEXRLcULsqNQSGkOvPJJhvAvsOSe0Zp2ZjrS0HJESXYjCkDJqO3FQj+ afdK8i1chXufFmp6DXnWXJWBV/Ga0bqQyU2R1lCe161gFkfYfk2E6BlXnW5r67su yu2TWhsbZctx7P4K02bqUFSNzOtJ56+PVprrwRFwlWxVJinU57trJaUu1w23HmkD YhSTRjVEXhMidJvxGSnSq7YmW+04/qXAN6OIoCdJVxQFDJJ9tcWlJEaBgTvu8wsJ aoZ3AdRexFQLZln9wzClttjVnn90AcqvOadKp4fkJhUqVn7DAumBFsR4sUQcM2qX pQd8OKxQixKtGhQhXrQtL7A1B6pTiZIo0Cb8RlWL6uNBwTtzsHl+BI5ySQAs/v34 Ed6xuBz4IkK7gABlkV8LiCF/tCSY1pWmoG/WdiqG6f6oidoBVUNxcu76zERI/Q8K 79JNqmnWv9RQfGqdZEiAdyI9cLDjRV3CJwm1rv7+FVWI7sq0fVgas7zZbIJ6/di5 EjXDYcMgJ59PydJmxjyz =7LWo -----END PGP SIGNATURE----- --=-Qz2OKbu2Dou4b5FuZ1ff-- --===============9116637548970594774== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KWGVuLWRldmVs IG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMueGVuLm9yZwpodHRwczovL2xpc3RzLnhlbi5v cmcveGVuLWRldmVsCg== --===============9116637548970594774==--