Editing Diskless node (section)

===Centralized storage===

The use of central disk storage also makes more efficient use of disk storage. This can cut storage costs, freeing up capital to [[investment|invest]] in more reliable, modern storage technologies, such as [[RAID|RAID array]]s which support redundant operation, and [[storage area network]]s which allow hot-adding of storage without any interruption. Further, it means that losses of disk drives to mechanical or electrical failure—which are statistically highly probable events over a timeframe of years, with a large number of disks involved—are often both less likely to happen (because there are typically fewer disk drives that can fail) and less likely to cause interruption (because they would likely be part of RAID arrays). This also means that the nodes ''themselves'' are less likely to have hardware failures than [[rich client]]s.

Diskless nodes share these advantages with [[thin client]]s.

====Performance of centralized storage====

However, this storage efficiency can come at a price. As often happens in computing, increased storage efficiency sometimes comes at the price of decreased performance.

Large numbers of nodes making demands on the same server simultaneously can slow down everyone's experience. However, this can be mitigated by installing large amounts of [[random-access memory|RAM]] on the server (which speeds up read operations by improving [[Cache (computing)|caching]] performance), by adding more servers (which distributes the I/O workload), or by adding more disks to a RAID array (which distributes the ''physical'' I/O workload). In any case this is also a problem which can affect ''any'' client-server network to some extent, since, of course, rich clients also use servers to store user data.

Indeed, user data may be much more significant in size and may be accessed far more frequently than operating systems and programs in some environments, so moving to a diskless model will not ''necessarily'' cause a noticeable degradation in performance.

Greater [[network bandwidth]] (i.e. capacity) will also be used in a diskless model, compared to a rich client model. This does not necessarily mean that a higher capacity network infrastructure will need to be installed—it could simply mean that a higher proportion of the existing network capacity will be used.

Finally, the combination of network data transfer [[latency (engineering)|latencies]] (physically transferring the data over the network) and contention latencies (waiting for the server to process other nodes' requests before yours) can lead to an unacceptable degradation in performance compared to using local drives, depending on the nature of the application and the capacity of the network infrastructure and the server.