Oracle Direct Network File System Client in oracle 11g new features

This feature is implemented as a Direct Network File System (NFS) client as a part of Oracle RDBMS Kernel in Oracle Disk Manager library. NAS-based storage systems use NFS to access data. In Oracle Database 10g, NAS storage devices are accessed using the operating system provided kernel NFS driver, which require specific configuration settings to ensure its efficient and correct usage with Oracle.

The following are the major problems that arise in correctly specifying configuration parameters:

* NFS clients are very inconsistent across platforms and vary across operating system releases.

* The configuration parameters are difficult to tune. There are more than 20 NFS parameters and they have subtle differences across platforms.

* NFS client stack is designed for general purpose. Therefore, it contains features like file attribute management that are not required for Oracle.

* Oracle Direct NFS implements NFS version 3 protocol within the Oracle RDBMS kernel.

The following are the main advantages of implementing Oracle Direct NFS client functionality in Oracle RDBMS Kernel:

* It enables complete control over input-output paths to network file servers, resulting in predictable performance, simplified configuration management, and superior diagnostics.

* Its operations avoid the kernel NFS layer bottlenecks and resource limitations. However, the kernel is still used for network communication modules.

* It provides a common NFS interface for Oracle for potential use on all host platforms and supported NFS servers.

* It enables improved performance through load balancing across multiple connections to NFS servers and deep pipelines of asynchronous input-output operations with improved concurrency.