[ovs-dev] [Xen-devel] [PATCH V4] hotplug: add openvswitch script

[Roger Pau Monné]

On 02/05/13 17:32, steve_1991 at hushmail.com wrote:
> On Thu, May 2, 2013 at 11:17 AM, Roger Pau Monné <roger.pau at citrix.com> wrote:
>> On 02/05/13 17:09, agya naila wrote:
>>> Does any one have test this script performance with Xen live migration?
>>> what is the performance result compared with brctl. I hope any body want
>>> to share it. I want to use this script with my Xen 4.2.1 using xend/xm
>>> toostack.
>>
>> I have not tried it myself, but I'm not sure this will play nice with
>> xend/xm, AFAIK xend had a race regarding device destruction and hotplug
>> execution, that's one of the points why we call hotplug scripts from
>> libxl directly instead of calling them from udev. Any reason to use xm
>> instead of xl?
> 
> I think I should ask in separate email but anyways. Does xl with run_hotplug_scripts=0
> (forcing hotplug through udev) has race with udev?

AFAIK the hotplug script could be called by udev when the xenstore
entries are already gone, because xm and libxl (with
run_hotplug_scripts=0) removes the entries from xenstore, but has no
control of when udev calls the hotplug script.