Subject: Re: XEN3 on NetBSD 4.9.1 gets irresponsive.
To: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
From: Marcin Jessa <lists@yazzy.org>
List: port-xen
Date: 08/14/2006 10:04:57
On Monday 14 August 2006 00:46, YAMAMOTO Takashi wrote:
> > Howdy guys.
> >
> > I noticed huge problems with system response time on 4.99.1.
> > I upgraded my DOM0 kernel to 4.99.1 still running 3.99.21 on DOMU.
> > Now, every time I ran something using my CPU, like compiling new kernel,
> > the DOMU become very irresponsive. Things started take long time from
> > ping times rising to 100-200 ms between DOMU and DOM0 to time it took to
> > boot my DOMU.
> > Things came back to normal when I didn't use my DOMO CPU.
>
> it's normal with xen3 default scheduler setting.

So what is the default scheduler now? Is that SEDF ? Can't see anything in 
dmesg of XEN0 or XENU.
Should I try to put sched=bvt on the xen boot command line in grub.conf 
instead?

>
> > When I run 4.99.1 on both XEN0 and XENU the XENU was irresponsive
> > no metter if CPU usage on the XEN0 was 0 or 100%.
>
> i couldn't reproduce it.
> > One other guy on #NetBSD on freenode noticed the same problem.
> > In his case he was running 3.99.x on DOM0 and 4.9.1 on DOMU.
>
> same as which of the above?

I updated my sources again and the problem is gone.
Network I/O is still slow but only on high CPU utilization on XEN0 but not 
when the CPU is idle.

Cheers,
Marcin.