Towards minimalistic, virtualized content caches with minicache

Video comprises the majority of traffic on the Internet today, and most of it is delivered via Content Delivery Networks (CDNs) whose performance depends, to a large extent, on being able to deploy a (sometimes rather large) set of distributed content caches at different networks and geographical locations. Recently, ISPs have started deploying micro datacenters close to customers, giving the possibility to third parties to rent out this equipment. While such pay-on-demand infrastructure would allow CDNs to dynamically expand their capacity and improve their efficiency, a high performance, virtualized content cache would be needed for multiple tenants to be able to share such facilities. Towards this end we introduce Minicache, a Xen-based virtualized content cache prototype. A Minicache virtual machine has a small memory footprint (as small as 5MB in size), can boot in as little as 30 milliseconds, and can fill up a 10Gb pipe using data retrieved from storage devices.