<gh_stars>0
\begin{abstract}
Efficiently managing storage is important for virtualized computing 
environments. 
Its importance is magnified by developments such as cloud computing which 
consolidate many thousands of virtual machines (and their associated storage). 
The nature of this storage is such that there is a large amount of 
duplication between otherwise discreet virtual machines. 
Building upon previous work in content addressable storage, we have built a 
prototype for consolidating virtual disk images using a service-oriented file 
system. 
It provides a hierarchical organization, manages historical snapshots of 
drive images, and takes steps to optimize encoding based on partition type and 
file system. 
In this paper we present our experiences with building this prototype and 
using it to store a variety of drive images for QEMU and the Linux
Kernel Virtual Machine (KVM).
\end{abstract}
