[Openstack] Vm provision code flow in openstack

Deepak Jeswani1 dejeswan at in.ibm.com
Mon Apr 29 11:12:08 UTC 2013


Hello Michael,

Many thanks for your response. I somehow found this code base (in 
installed openstack instance) and I inserted debug steps (opening a log 
file and printing statements into it) to see if the code flows through the 
file (specifically file '/usr/share/pyshared/nova/compute/api.py' in 
function 'def _create_instance'). Also I checked stat of all files to see 
if they get accessed when I do the provisioning. But neither my debug 
worked nor I could get the access stat of file. 

So I have doubt. either these are not the files (but as you pointed out, 
these are the correct file) or I have to insert debug statements in source 
files and build them again to see effect.

Let me do changes in source code, build it and see what happens. If you 
have any comments please let me know.

Thanks

Regards
Deepak



From:   Michael Still <mikal at stillhq.com>
To:     Deepak Jeswani1/India/IBM at IBMIN
Cc:     OpenStack general mailing list <openstack at lists.launchpad.net>
Date:   04/29/2013 03:57 PM
Subject:        Re: [Openstack] Vm provision code flow in openstack
Sent by:        mikalstill at gmail.com



So, there are a few things which happen here. VM provisioning is handled 
by the compute driver (checkout run_instance in nova/compute/manager.py). 
Scheduling however is handled by the scheduler, which has a plugin system 
(checkout nova/scheduler/*).

Also, you'd be better off browing git for the source code (
http://github.com/openstack/nova.git) instead of the system installed 
files.

Cheers,
Michael


On Mon, Apr 29, 2013 at 7:14 PM, Deepak Jeswani1 <dejeswan at in.ibm.com> 
wrote:
Hello everyone, 

I am trying to understand the flow of control in code in openstack for 
provisioning a VM. I want to understand it in order to do modify scheduler 
module as per our requirements. 

I have found the code base which, if I am not wrong, is kept in 
/usr/share/pyshared/nova/* directory but I can't see .py files getting 
accessed or executed if I provision a VM. 

Can someone please help me to understand the flow of code or give me 
pointers from where I can understand it. I hope even if I know the 
starting point (REST handler for VM provisioning call) in code then I will 
be able to trace it. 

Thanks 

Regards
Deepak 

Deepak Jeswani 
Software Engineer, 
Distributed Systems Group, 
IBM Research-India 


_______________________________________________
Mailing list: https://launchpad.net/~openstack
Post to     : openstack at lists.launchpad.net
Unsubscribe : https://launchpad.net/~openstack
More help   : https://help.launchpad.net/ListHelp


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack/attachments/20130429/c78a2a51/attachment.html>


More information about the Openstack mailing list