The advances in network technology and the growth of

the Internet together with upcoming new applications like

peer-to-peer (P2P) networks have led to an exponential

growth of the stored data volume. The key to manage this

data explosion seems to be the consolidation of storage systems

inside storage area networks (SANs) and the use of a

storage virtualization solution that is able to abstract from

the underlying physical storage system.

In this paper we present the first measurements on an

out-of-band storage virtualization system and investigate

its performance and scalability compared to a plain SAN.

We show in general that a carefully designed out-of-band

solution has only a very minor impact on the CPU usage

in the connected servers and that the metadata management

can be efficiently handled. Furthermore we show that

the use of an adaptive data placement scheme in our virtualization

solution V:Drive can significantly enhance the

throughput of the storage systems, especially in environments

with random access schemes.