Re: [PATCH] time,virt: resync steal time when guest & host lose sync

From: Wanpeng Li
Date: Thu Aug 11 2016 - 06:11:41 EST


2016-08-11 0:52 GMT+08:00 Rik van Riel <riel@xxxxxxxxxx>:
> On Wed, 10 Aug 2016 07:39:08 +0800
> Wanpeng Li <kernellwp@xxxxxxxxx> wrote:
>
>> The regression is caused by your commit "sched,time: Count actually
>> elapsed irq & softirq time".
>
> Wanpeng, does this patch fix your issue?

I test this against kvm guest (nohz_full, four vCPUs running on one
pCPU, four cpuhog processes running on four vCPUs).
before this fix patch:
vCPU0's st is 100%, other vCPUs' st are ~75%.
after this fix patch:
all vCPUs' st are ~85%.
However, w/o commit "sched,time: Count actually elapsed irq & softirq
time", all vCPUs' st are ~75%.

Regards,
Wanpeng Li