From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joanna Rutkowska Subject: Re: A clocksource question Date: Sat, 13 Mar 2010 10:58:37 +0100 Message-ID: <4B9B61CD.80401@invisiblethingslab.com> References: <4B962748.90609@invisiblethingslab.com> <4B9A8FDE.8070506@invisiblethingslab.com> <4B9AB126.1070406@goop.org> <201003122256.02254.tobias.geiger@vido.info> <4B9AB9FE.8070601@goop.org> <4B9AABB9.7030906@invisiblethingslab.com> <4B9AAE6A.6050801@invisiblethingslab.com> <4B9AD2DD.90907@goop.org> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1656535641==" Return-path: In-Reply-To: <4B9AD2DD.90907@goop.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jeremy Fitzhardinge Cc: Tobias Geiger , xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --===============1656535641== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig685C459B0D6C442583AB8AD1" This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig685C459B0D6C442583AB8AD1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 03/13/2010 12:48 AM, Jeremy Fitzhardinge wrote: > On 03/12/2010 01:13 PM, Joanna Rutkowska wrote: >> >>> The "clocksource tsc unstable" messages trouble me too BTW. They seem= to >>> appear before the hrtimer "interrupt too slow" messages. >>> >>> =20 >> But this "tsc unstable" message does not seem to be so critical, >=20 > They're nothing to worry about. >=20 >> e.g. I >> just started my system (xen clocksource) and started a VM, and got the= >> usual hrtimer "slow interrupt" warning, and then all the symptoms >> started, but there no "tsc unstables" warning in dmesg. >> >> However, I previously missed another message, that seem to occur at th= e >> very beginning of the system life (before I started any other VMs): >> >> Marking TSC unstable due to TSC halts in idle >> =20 >=20 > That doesn't matter because it doesn't use the tsc clocksource. The Xe= n > clocksource uses the tsc hardware register, but it isn't subject to the= > same constraints that the tsc clocksource is. The tsc clocksource > calibration is probably getting confused by being on a vcpu. >=20 In the meantime found a similar thread on KVM: http://www.mail-archive.com/kvm@vger.kernel.org/msg22925.html and also a patch suggested there: http://www.mail-archive.com/kvm@vger.kernel.org/msg23491.html Don't have time to try the patch right now, but courious to hear your opinion in the meantime... Thanks, joanna. --------------enig685C459B0D6C442583AB8AD1 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org/ iEYEARECAAYFAkubYdMACgkQORdkotfEW86P9wCfbb9V/4d4LG0aBPb2Fe7K1fVb AqcAnRZfoprBDEgwvqpa3nKhLvAKzDxB =xIOp -----END PGP SIGNATURE----- --------------enig685C459B0D6C442583AB8AD1-- --===============1656535641== 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.xensource.com http://lists.xensource.com/xen-devel --===============1656535641==--