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[Balamurugan V G <balamuruganvg@xxxxxxxxx>]

Thanks for the response. I have the images as .img in the web server which
is external to OpenStack nodes. But while I create the image in Horizon, I
set the format to QCOW2. So once th image is created it shows as QCOW2.
Then the instance is launched from this QCOW2 image.

Do you mean that I original image should also be QCOW2?

I will also try the settings which you recommended.

Regards,
Balu

On Tue, Mar 5, 2013 at 4:50 PM, Pádraig Brady <P@xxxxxxxxxxxxxx> wrote:

> On 03/05/2013 11:03 AM, Balamurugan V G wrote:
> > Hi,
> >
> > I have a Folsom 2012.2 3 nodes setup like the one specified at
> https://github.com/mseknibilel/OpenStack-Folsom-Install-guide/blob/master/OpenStack_Folsom_Install_Guide_WebVersion.rst.
> Each node has a 1Tb hard disk with no raid.
> >
> > Be it the image creation or the Instance creation, takes a long
> time(factor of the disk size of the image), about 15mins for a 20gb image.
> I can understand the slow image creation due to the http transfer of the
> file from a seperate web server hosting my images to the controller node.
> But even the instance creation takes that much or even a bit longer. I see
> that the image is copied from the Controller to Compute node and multiple
> copies are make in the compute node. So all this takes long an dis
> proportional to the image size. Is there any way to speed up this process?
> Is a SAN based backend the only way to go?
>
> It sounds like you're using raw images throughout?
> You might consider using qcow2 images in glance.
> Then you can avoid the conversion to raw in the libvirt base
> directory by setting force_raw_images=False in nova.conf
> That will avoid some of the initial caching penalty.
>
> Ensuring that you have use_cow_images=True set,
> with use CoW images for the instances and improve
> instance startup latency.
>
> Details of the operations and tradeoffs involved are at:
> http://www.pixelbeat.org/docs/openstack_libvirt_images/
>
> thanks,
> Pádraig.
>
>