Ingo Molnar wrote: > * Zachary Amsden <[EMAIL PROTECTED]> wrote: > > >> On Mon, 2007-10-29 at 20:10 -0300, Glauber de Oliveira Costa wrote: >> >>> From: Glauber de Oliveira Costa <[EMAIL PROTECTED]> >>> >>> tsc is very good time source (when it does not have drifts, does not >>> change it's frequency, i.e. when it works), so it should have its rating >>> raised to a value greater than, or equal 400. >>> >>> Since it's being a tendency among paravirt clocksources to use values >>> around 400, we should declare tsc as even better: So we use 500. >>> >> Why is the TSC better than a paravirt clocksource? In our case this >> is definitely inaccurate. Paravirt clocksources should be preferred >> to TSC, and both must be made available in hardware for platforms >> which do not support paravirt. >> > > if it's inaccurate why are you exposing it to the guest then? Native > only uses the TSC if it's safe and accurate to do so. >
It is used as part of the Xen clocksource as a short term extrapolator, with correction parameters supplied by the hypervisor. It should never be used directly. J ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel