Quantum 3.1.4.1 manual Performance, Fault tolerance, Load Balancing Client Scalability

StorNext File System Tuning

Distributed LAN Client Vs. Legacy Network Attached Storage

Performance

•Performance

•Fault Tolerance

•Load Balancing

•Client Scalability

•Robustness and Stability

•Security Model Consistency

DLC outperforms NFS and CIFS for single-stream I/O and provides higher aggregate bandwidth. For inferior NFS client implementations, the difference can be more than a factor of two. DLC also makes extremely efficient use of multiple NICs (even for single streams,) whereas legacy NAS protocols allow only a single NIC to be used. In addition, DLC clients communicate directly with StorNext metadata controllers instead of going through an intermediate server, thereby lowering IOP latency.

Fault tolerance

DLC handles faults transparently, where possible. If an I/O is in progress and a NIC fails, the I/O is retried on another NIC (if one is available). If a Distributed LAN Server fails while an I/O is in flight, the I/O is retried on another server (if one is running). When faults occur, applications performing I/O will experience a delay but not an error, and no administrative intervention is required to continue operation. These fault tolerance features are automatic and require no configuration.

Load Balancing

Client Scalability

DLC automatically makes use of all available Distributed LAN Servers in an active/active fashion, and evenly spreads I/O across them. If a server goes down or one is added, the load balancing system automatically adjusts to support the new configuration.

As the following table shows, DLC supports a significantly larger number of clients than legacy NAS protocols:

24 StorNext File System Tuning Guide