Quantum 6-01376-07 manual Largest Tested Configuration, Number of Clients Tested via, Simulation

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Performance

Fault tolerance

Load Balancing

Client Scalability

Robustness and Stability

StorNext File System Tuning Distributed LAN Client Vs. Legacy Network Attached Storage

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.

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.

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:

Largest Tested Configuration

 

NFS

CIFS

DLC

Number of Clients Tested (via

 

 

 

4

4

1000

simulation)

 

 

 

 

 

 

 

The code path for DLC is simpler, involves fewer file system stacks, and is not integrated with kernel components that constantly change with every operating system release (for example, the Linux NFS code).

StorNext File System Tuning Guide

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ExtNrotS Copyright Statement Contents Underlying Storage System StorNext File System TuningRAID Cache Configuration RAIDWrite-BackCaching RAID Read-Ahead Caching RAID Level, Segment Size, and Stripe Size Direct Memory Access DMA I/O Transfer File Size Mix and Application I/O CharacteristicsBuffer Cache NFS / Cifs Metadata Controller System Metadata NetworkStripe Groups FSM Configuration File SettingsAffinities ExampleBufferCacheSize StripeBreadthThreadPoolSize InodeCacheSizeForcestripeAlignment FsBlockSizeSnfs Tools JournalSizeStorNext File System Tuning Metadata Controller System StorNext File System Tuning Metadata Controller System StorNext File System Tuning Metadata Controller System Latency-testindex-number seconds Mount Command Options Distributed LAN Disk Proxy Networks Hardware ConfigurationSnfs External API Network Configuration and Topology Multi-NIC Hardware and IP Configuration Diagram Distributed LAN Client Vs. Legacy Network Attached Storage Distributed LAN ServersNumber of Clients Tested via Largest Tested ConfigurationSimulation Consistent Windows Memory RequirementsStorNext File System Tuning Windows Memory Requirements Sample FSM Configuration File MAXStripeBreadth StorNext File System Tuning Sample FSM Configuration File StorNext File System Tuning Sample FSM Configuration File StorNext File System Tuning Sample FSM Configuration File