From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: Re: [PATCH v13] tolerate jitter in cpu_khz calculation to avoid TSC emulation Date: Wed, 13 Mar 2019 17:02:02 +0100 Message-ID: <20190313170202.20f8bc75.olaf@aepfle.de> References: <20190313082855.14106-1-olaf@aepfle.de> <5C88CAEF020000780021DFA6@prv1-mh.provo.novell.com> <20190313145144.64b0f9fd.olaf@aepfle.de> <5C891584020000780021E2C0@prv1-mh.provo.novell.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============6755165898999293148==" Return-path: Received: from us1-rack-dfw2.inumbo.com ([104.130.134.6]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1h46KW-0001Oj-HZ for xen-devel@lists.xenproject.org; Wed, 13 Mar 2019 16:02:09 +0000 In-Reply-To: <5C891584020000780021E2C0@prv1-mh.provo.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" To: Jan Beulich Cc: Andrew Cooper , xen-devel , Wei Liu , Ian Jackson , Roger Pau Monne List-Id: xen-devel@lists.xenproject.org --===============6755165898999293148== Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/hw8gEPmjB1DP4G8=ExPoRN_"; protocol="application/pgp-signature" --Sig_/hw8gEPmjB1DP4G8=ExPoRN_ Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Am Wed, 13 Mar 2019 08:36:52 -0600 schrieb "Jan Beulich" : > Why is there this big step between 199 and 200? And why does an > initial value of 200 get handled the same as an initial value of 0, but > then 400 doesn't get handled this same way again? And (seeing the > last row I've added now) how is the result staying in range? Well, capping the PPM-to-khz value may not work anyway as outlined in the other email about missing 'drift'. We may just leave that PPM value as is, or reduce it upfront by a certain amount. Since right now the real drift is not considered, the plain 500PPM may work or not in the worst case. I will think about if and how drift should be part of the picture. Olaf --Sig_/hw8gEPmjB1DP4G8=ExPoRN_ Content-Type: application/pgp-signature Content-Description: Digitale Signatur von OpenPGP -----BEGIN PGP SIGNATURE----- iF0EARECAB0WIQSkRyP6Rn//f03pRUBdQqD6ppg2fgUCXIkpegAKCRBdQqD6ppg2 fo39AKCGnfAV1kC1IdxFtGDXUuHM6jaY2gCgkarQ9//99SS3gMrsCHUe9dW0+8g= =fGR/ -----END PGP SIGNATURE----- --Sig_/hw8gEPmjB1DP4G8=ExPoRN_-- --===============6755165898999293148== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KWGVuLWRldmVs IG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMueGVucHJvamVjdC5vcmcKaHR0cHM6Ly9saXN0 cy54ZW5wcm9qZWN0Lm9yZy9tYWlsbWFuL2xpc3RpbmZvL3hlbi1kZXZlbA== --===============6755165898999293148==--