Storage design

As compute hardware has become less expensive over the last few years, fewer and fewer workloads are constrained by a lack of processor or memory performance. Instead, most workloads are tuned so that they are constrained on I/O-particularly storage I/O. OpenStack workloads typically separate the operating system storage from the application storage and Cinder and the different object storage projects provide mechanisms for presenting many different kinds of storage with a single interface. This capability allows tenants to choose the storage which matches their application's requirements. In addition to Cinder providing persistence for applications, block storage and object storage also provide storage persistence for instances and allow for instance live migration, backup, and recovery.

Ephemeral storage

Ephemeral storage is the storage that is consumed when a Glance image is copied locally to a compute node to instantiate a virtual instance. Glance images are typically...