Performance analysis of storage area networks using high-speed LAN interconnects

Storage area networks (SANs) are an emerging data communications platform which interconnects servers an storage devices (such as disks, disk arrays, and tape drives) to create a pool of storage that users can access directly. SANs eliminate the bandwidth bottlenecks and scalability limitations imposed by previous SCSI bus-based architectures and LAN connections between servers and the stored data. This networking approach reports benefits such as computer clustering, topological flexibility, fault tolerance, high availability, and remote management. The prominent technology for implementing SANs is the fibre channel, due to the suitability of this technology for storage networking. Other technologies for high performance interconnects have also been developed. These interconnects provide switch-based networks with links transferring data at more than 1 Gigabit per second, being mainly used in the LAN environments. We analyze whether these high-speed LAN technologies could also be an interesting alternative to storage networking. We perform this analysis using real-world I/O traces. The main conclusion from our study is that most of the messages present the base network latency, meaning that the network is not heavily loaded. Moreover the response time is, in general, acceptable, being dominated by the time disks need to process the requests.