RE: [Xen-devel] System time monotonicity

["Ian Pratt" <Ian.Pratt@xxxxxxxxxxxx>]

> > Try booting with one physical (maxcpus=1 on the xen command 
> line) CPU 
> > just to verify this isn't a multi-CPU issue.
> 
> Can reproduce:
> 
> [1]> 0xfffffffed5cc0120::print kthread_t t_dhrtime 
> t_dhrtime_cpu t_dhrtime_tsc t_dhrtime_vers t_dhrtime = 
> 0x509957b7c2 t_dhrtime_cpu = 0x1 t_dhrtime_tsc = 0xf6f1529888 
> t_dhrtime_vers = 0x132
> 
> [1]> 0x509957b7c2 - 0x000000509957039e=D
>                 46116

Please can you try hitting 't' a few times on the Xen debug console
(again, maxcpus=1)

If you're seeing time jump back on a single CPU, it must mean that the
TSC ran quicker during the current period than what it was calibrated to
be running at in the last period. It's worth adding some debuging
printk's to the calibration code in Xen to see what it thinks is going
on from one calibration period to the next.

Thanks,
Ian

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel