If Nova and Glance are properly configured, it should only require a quick clone of the Glance image to create your Nova ephemeral image. Have you double-checked your configuration against the documentation [1]? What version of OpenStack are you using?
To answer your questions: > - From Ceph point of view. does COW works cross pool i.e. image from glance > pool ---> (cow) --> instance disk on nova pool Yes, cloning copy-on-write images works across pools > - Will a single pool for glance and nova instead of separate pool . will help > here ? Should be no change -- the creation of the clone is extremely lightweight (add the image to a directory, create a couple metadata objects) > - Is there any tunable parameter from Ceph or OpenStack side that should be > set ? I'd double-check your OpenStack configuration. Perhaps Glance isn't configured with "show_image_direct_url = True", or Glance is configured to cache your RBD images, or you have an older OpenStack release that requires patches to fully support Nova+RBD. [1] http://docs.ceph.com/docs/master/rbd/rbd-openstack/ -- Jason Dillaman ----- Original Message ----- > From: "Vickey Singh" <vickey.singh22...@gmail.com> > To: ceph-users@lists.ceph.com, "ceph-users" <ceph-us...@ceph.com> > Sent: Monday, February 8, 2016 9:10:59 AM > Subject: [ceph-users] Tips for faster openstack instance boot > Hello Community > I need some guidance how can i reduce openstack instance boot time using Ceph > We are using Ceph Storage with openstack ( cinder, glance and nova ). All > OpenStack images and instances are being stored on Ceph in different pools > glance and nova pool respectively. > I assume that Ceph by default uses COW rbd , so for example if an instance is > launched using glance image (which is stored on Ceph) , Ceph should take COW > snapshot of glance image and map it as RBD disk for instance. And this whole > process should be very quick. > In our case , the instance launch is taking 90 seconds. Is this normal ? ( i > know this really depends one's infra , but still ) > Is there any way , i can utilize Ceph's power and can launch instances ever > faster. > - From Ceph point of view. does COW works cross pool i.e. image from glance > pool ---> (cow) --> instance disk on nova pool > - Will a single pool for glance and nova instead of separate pool . will help > here ? > - Is there any tunable parameter from Ceph or OpenStack side that should be > set ? > Regards > Vickey > _______________________________________________ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
