On 08/26/2010 12:43 AM, Glauber Costa wrote:
This patch proposes a common steal time implementation. When no steal time is accounted, we just add a branch to the current accounting code, that shouldn't add much overhead. When we do want to register steal time, we proceed as following: - if we would account user or system time in this tick, and there is out-of-cpu time registered, we skip it altogether, and account steal time only. - if we would account user or system time in this tick, and we got the cpu for the whole slice, we proceed normaly. - if we are idle in this tick, we flush out-of-cpu time to give it the chance to update whatever last-measure internal variable it may have. This approach is simple, but proved to work well for my test scenarios. in a UP guest on UP host, with a cpu-hog in both guest and host shows ~ 50 % steal time. steal time is also accounted proportionally, if nice values are given to the host cpu-hog. A cpu-hog in the host with no load in the guest, produces 0 % steal time, with 100 % idle, as one would expect.
The scheduler people and lkml need to be copied on this patch. Since s390 does steal time (I think?), can this code be shared? -- error compiling committee.c: too many arguments to function -- 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
