Traditionally, Linux semantics require that read and write operations on a file occur in a serialized order. Because of this, a file system must enforce strict ordering of overlapping read and write operations. However, databases do not usually require this level of control and implement concurrency control internally, without using a file system for order enforcement.

The Veritas Concurrent I/O feature removes these semantics from the read and write operations for databases and other applications that do not require serialization.