Direct NFS (DNFS) is an Oracle Database 11g implementation of NFS client that runs as part of the Oracle Database 11g engine. Through this integration, the Oracle database engine optimizes the I/O access path to NFS server to provide improved scalability and reliability. In previous Oracle versions, the I/O operations to the NFS server were done through the native NFS client of the Operating system. Even though the native NFS client implementations evolved over the last few years, the features & configuration varied across operating systems and the end user experience was not uniform across them. Each operating system needed a special set of NFS mount options to maximize its performance.
Oracle Direct NFS client provides uniform features across all operating systems, independent of native NFS client implementation. Manual tuning of NFS client parameters and mount options are no longer required to maximize the performance. Direct NFS client is available across all operating systems that Oracle Database 11g supports including Microsoft Windows.
Direct NFS client also improves NFS performance by incorporating Oracle specific tuning enhancements and by eliminating unnecessary overhead of OS kernel NFS implementations.
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