The time-worn Network File System (NFS), designed by Sun Microsystems Inc. of Santa Clara, CA, over twenty years ago has been getting a much needed makeover. NFS, of course, helps systems to connect so that you can obtain a single view of all files in an environment. But as it was designed for networks circa 1984, its performance left a lot to be desired.
Enter NFSv4.1 which includes a key component known as parallel NFS (pNFS). pNFS enables high-speed data movement between machines.
"The most significant component of NFS V4.1 is the inclusion of pNFS which represents the first major performance upgrade to NFS in over a decade," said Matt Reid, director of product marketing at Panasas Inc. of Fremont, CA. "pNFS represents the standardization of parallel IO and allows clients to access storage devices directly and in parallel thus eliminating the scalability and performance issues associated with NFS servers deployed today."
pNFS let's you do several things. You can stripe a single file across multiple NFS servers, which is essentially the same as RAID0. While RAID0 boosts performance by allowing multiple disk drives to serve up data to in parallel, pNFS takes the concept and extends it to multiple storage devices connected to the NFS client over a network. Even if files are too small to stripe, those files can be distributed across multiple NFS servers. As a result, it provides statistical load balancing. Further, with a capable cluster of NFS servers and a backend file system, files or ranges within files can be relocated transparent to the applications accessing data over pNFS.
This is achieved by the separation of data and metadata, i.e. pNFS moves the metadata server out of the data transfer path. It is actually the same thing that Panasas does in its ActiveStor Parallel Storage Clusters.
At its heart is the third generation ActiveScale OS with the PanFS parallel file system which turns files into smart data objects and then dynamically distributes data transfer operations across Panasas StorageBlade modules. This object-based storage clustering architecture enables parallel data paths between StorageBlade modules and client nodes. According to Reid, the ActiveScale OS dramatically lowers the cost of managing data storage by supporting a massive expansion in data capacity within a single, easily managed namespace.
"Panasas has been a leader in the development of the pNFS standard from the very beginning," said Reid.
Panasas CTO Garth Gibson, for example, co-authored the standard's initial problem statement in 2004. Since then, the company has provided substantial technical input to the NFSv4 committee working on pNFS. In addition, it is directly contributing source code to the Linux NFS client and server as well as to the Linux object storage driver, iSCSI driver, and SCSI stack.
Most importantly, the architecture for the pNFS proposal was derived from the Panasas DirectFLOW parallel protocol, which is a core component utilized by the Panasas PanFS parallel file system.
"The Panasas DirectFLOW protocol used in our ActiveStor Parallel Storage Clusters currently provides essentially all of the functionality expected to be available in the NFSv4.1 later this year," said Reid.
That leads him to assert that his company offers the smoothest transition to fully compliant pNFS-compatible storage systems. Panasas and a host of other major storage vendors will begin shipping such systems next year.
"Users and application developers can take immediate advantage of the high performance and superior ease of use of the only production-proven parallel storage system today, the ActiveStor Parallel Storage Clusters from Panasas," said Reid.
Panasas, of course, has been shipping parallel storage systems to Fortune 500 companies and major government institutions since 2003. It sees the fact that its architecture has essentially been incorporated into the NFS protocol as a significant validation.
"We are very excited that the Panasas architecture is being adopted as standard by the storage industry as it validates the importance of parallel storage and our vision for the future of file storage," said Reid. "NFS V4.1 will finally give users a reason to aggressively migrate to the latest version of NFS, primarily because of the dramatic performance benefits of pNFS."
This is good news for the user community as a whole. After all, there are a number of competing proprietary and open-source parallel file systems in existence. Standardization of parallel IO through pNFS will allow users to reap the benefits of parallel storage systems by choosing best-of-breed solutions without having concerns over vendor lock-in.
"pNFS will accelerate the adoption of parallel storage to a broad range of customers, from traditional HPC, to commercial HPC, to web infrastructure and media distribution," said Reid. "The future of file storage is parallel and NFS V 4.1 is the start of this major industry transformation."
Article courtesy of Enterprise IT Planet