On 13:42 Aug 11, Brian Rosmaita wrote: > On 8/7/15, 1:07 PM, "Jay Pipes" <[email protected]> wrote: > > >So, here's the crux of the issue. Nova and Cinder **do not want to speak > >the Glance REST API** to either upload or download image bits from > >storage. Streaming image bits through the Glance API endpoint is a > >needless and inefficient step, and Nova and Cinder would like to > >communicate directly with the backend storage systems. > > Exactly why do you want to communicate directly with the backend storage > systems? Streaming image bits through Glance appears to be "needless and > inefficient", but if an end-user is booting 1K instances from some custom > image, Glance's image cache makes an enormous difference in delivery time. > > So I'm curious about what exactly the use cases for direct backend storage > communication are, and why Glance can't meet them.
I don't think you read my email carefully in this discussion... Streaming bits to Glance with cache or not will *never* outperform a block storage backend that can do a copy on write of an image when that storage backend is also the glance backend store. While Glance is copying the bits, the block storage backend is able to create a reference pointer of that image, to the new volume and move on. No copying necessary. -- Mike Perez __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
