On 10/15/07, Gerd Hoffmann <[EMAIL PROTECTED]> wrote: > > Host should know. Well, I hope. Dunno whenever one really can be sure > in all cases given all the different CPUs and tsc implementations.
In the same way we can be sure about hardware for everything else: Well... not being _quite_ sure ;-) > With VT you can attempt to make that invisible to the guest using the > tsc offset field. Probably svm can do that too (didn't check docs > though). kvm-lite can't (what is the status btw?). Xen "solves" that > by not doing power management *evil grin*. Well, my previous understanding was that if the CPU marks the tsc as stable, it _won't_ stop even in C3, and it was done this way exactly to make sure there are a stable source for timing. But it does not really matter. We have two options: * Not considering tsc stable at all if sleeps, and then using the tsc just for adjustments. * Considering the tsc stable, but taking the time the cpu spend sleeping into account, and returning some sorf of "return tsc + total_time_spent_sleeping_in_so_deep_sleep_states_such_as_C3" . I specially liked the naming. > Nevertheless it is probably much easier to go with pv timers (or maybe > emulate hpet timers). At this time, I am for pv timers. (Why would I have written it in the first place??). But indeed, a discussion about the emulation alternative is healthy. -- Glauber de Oliveira Costa. "Free as in Freedom" http://glommer.net "The less confident you are, the more serious you have to act." ------------------------------------------------------------------------- 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
