Re: [Xen-users] Domain 0 reboot when network flow is heavy

[Tom Mornini <tmornini@xxxxxxxxxxxxxx>]

Hello Xin.

In our case, the disk I/O load was always in the DomU (via a  
passthrough block device from Dom0), and was always associated with  
high network traffic, as our SAN is ethernet attached (AoE, not iSCSI).
We can crash the system through DomU disk I/O and associated network  
traffic alone. Accessing /proc/slabinfo greatly exacerbated the problem.
P.S. You're missing 'cat' in the script your showed:

!#/bin/sh
while [ 1 ] do
cat /proc/slabinfo >> ./slabinfo.txt
end

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On Jun 27, 2007, at 3:39 AM, Xin Chen wrote:

> Thanks Tom,
>
> I did these experiments on domain 0 today:
> First, I shutdown the guest systems running on domain 0, in case  
> domain 0 reboots.
> 1, write a script:
> !#/bin/sh
> while [ 1 ] do
> /proc/slabinfo >> ./slabinfo.txt
> end
>
> then keep this script running around 20 mins, until slabinfo.txt  
> about 4gb, domain 0 still running ok.
> 2, choose a 10gb file called temp, and do scp
> #scp temp localhost:/tmp/temp
> copying speed: 25mb/s, domain 0 still running ok.
>
> 3, again, like yesterday, scp a large file from remote server to  
> domain 0.   I did it twice, and domain 0 still running ok.
> I am not sure what it tells, I need to test again. Just may give a  
> idea that it only happens when there is a guest running???
> xin
>
>
>
> Tom Mornini wrote:
>
> > This sounds very similar to bugs we've seen with Xen version  
> > before 3.1
> > We believe the problem to be disk I/O related, but in our   
> > environment, disk I/O is also network I/O, so it's hard to tell.
> > We believe this problem to be corrected in 3.1, but we still  
> > haven't  done enough testing to satisfy ourselves entirely on this.
> > See this previous thread:
> >
> > http://lists.xensource.com/archives/html/xen-users/2007-03/ 
> > msg00073.html

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