Messages in this thread |  | | | Date | Wed, 14 Mar 2007 13:26:10 -0700 | | From | Dan Hecht <> | | Subject | Re: Stolen and degraded time and schedulers |
| |
>>> How is cpustat->steal used? How does it get out to usermode? >>> >> Via /proc/stat, used by modern 'top', maybe other utilities. It is >> useful to users who want to see where the time is really going from >> inside a guest when running on a (para)virtual machine. >> >> I believe previous set of xen paravirt-ops patches already handled >> cases #2 and #3 (but no longer do since switching to clockevents), and >> the old vmitime code did also. Obviously, we need revamp this stuff >> to make it fit in with the new clockevents/hrtimer way of doing things. > > I added stolen time accounting to xen-pv_ops last night. For Xen, at > least, it wasn't hard to fit into the clockevent infrastructure. I just > update the stolen time accounting for each cpu when it gets a timer > tick; they seem to get a tick every couple of seconds even when idle. >
Sounds good. I don't see this in your patchset you sent yesterday though; did you add it after sending out those patches? if so, could you forward the new patch? does it explicitly prevent stolen time from getting accounted as user/system time or does it just rely on NO_HZ mode sort of happening to work that way (since the one shot timer is skipped ahead for missed ticks)?
thanks, Dan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |