Re: xm pause causing lockup

[Kip Macy <kip.macy@gmail.com>]

I haven't tracked down the problem yet, but I thought the following
was sufficiently interesting to post:

kmacy@curly while (1)
while? xm list
while? sleep 5
while? end
Name              Id  Mem(MB)  CPU  State  Time(s)  Console
Domain-0           0      507    0  r----     67.9        
xen-vm2            1      128    1  r----      4.0    9601
Name              Id  Mem(MB)  CPU  State  Time(s)  Console
Domain-0           0      507    0  r----     68.1        
xen-vm2            1      128    1  r----      4.0    9601
Name              Id  Mem(MB)  CPU  State  Time(s)  Console
Domain-0           0      507    0  r----     68.3        
xen-vm2            1      128    1  r----      4.0    9601
Name              Id  Mem(MB)  CPU  State  Time(s)  Console
Domain-0           0      507    0  r----     68.5        
xen-vm2            1      128    1  r----      4.0    9601
Name              Id  Mem(MB)  CPU  State  Time(s)  Console
Domain-0           0      507    0  r----     68.7        
xen-vm2            1      128    1  r----      4.0    9601
Name              Id  Mem(MB)  CPU  State  Time(s)  Console
Domain-0           0      507    0  r----     68.9        
xen-vm2            1      128    1  r----      4.0    9601

xen-vm2 is always shown as running, but its time is not increasing.

               -Kip



On 4/13/05, Kip Macy <kip.macy@gmail.com> wrote:
> On 4/13/05, Keir Fraser <Keir.Fraser@cl.cam.ac.uk> wrote:
> > Probably easiest way to trace this is with printk's in Xen. The guts of
> > the work is done by domain_pause_by_systemcontroller() in xen/sched.h.
> > This in turn calls domain_sleep() in common/schedule.c.
> 
> I traced through that code a while back when trying to decide what to
> call from the int3 handler.
> 
> A particularly
> > interesting place to look will be teh synchronous spin loop at the end
> > of domain_sleep -- if the paused domain isn't descheduled for some
> > weird reason then the spin loop would never exit and domain0 would
> > hang.
> 
> Good point. It will be interesting to see.
> 
> I sometimes wonder if I should keep some of the buggy versions of
> FreeBSD around for regression testing as they trigger some interesting
> behaviours in xen and xend.
> 
>            -Kip
>