On Wed, 2012-10-17 at 21:14 +0400, Glauber Costa wrote: > On 10/17/2012 06:23 AM, Michael Wolf wrote: > > In the case of where you have a system that is running in a > > capped or overcommitted environment the user may see steal time > > being reported in accounting tools such as top or vmstat. This can > > cause confusion for the end user. To ease the confusion this patch set > > adds the idea of consigned (expected steal) time. The host will separate > > the consigned time from the steal time. The consignment limit passed to the > > host will be the amount of steal time expected within a fixed period of > > time. Any other steal time accruing during that period will show as the > > traditional steal time. > > > > TODO: > > * Change native_clock to take params and not return a value > > * Change update_rq_clock_task > > > > Changes from V1: > > * Removed the steal time allowed percentage from the guest > > * Moved the separation of consigned (expected steal) and steal time to the > > host. > > * No longer include a sysctl interface. > > > > You are showing this in the guest somewhere, but tools like top will > still not show it. So for quite a while, it achieves nothing. > > Of course this is a barrier that any new statistic has to go through. So > while annoying, this is per-se ultimately not a blocker. > > What I still fail to see, is how this is useful information to be shown > in the guest. Honestly, if I'm in a guest VM or container, any time > during which I am not running is time I lost. It doesn't matter if this > was expected or not. This still seems to me as a host-side problem, to > be solved entirely by tooling. > What tools like top and vmstat will show is altered. When I put time in the consign bucket it does not show up in steal. So now as long as the system is performing as expected the user will see 100% and 0% steal. I added the consign field to /proc/stat so that all time accrued in the period is accounted for and also for debugging purposes. The user wont care about consign and will not see it. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
