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

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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:

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Contents StorNext Copyright Statement Contents Contents StorNext File System Tuning Underlying Storage SystemRAID Write-Back RAID Cache ConfigurationCaching RAID Read-Ahead RAID Level, Segment Size, and Stripe Size File Size Mix and Application I/O Characteristics Buffer Cache NFS / CifsSnfs and Virus Checking Metadata NetworkMetadata Controller System FSM Configuration File Settings Stripe GroupsAffinities StripeBreadth InodeCacheSize BufferCacheSizeThreadPoolSize ForcestripeAlignment FsBlockSizeJournalSize FsBlockSize JournalSizeSnfs Tools StorNext File System Tuning Metadata Controller System StorNext File System Tuning Metadata Controller System Latency-testindex-number seconds Mount Command Options Snfs External API Distributed LAN Disk Proxy NetworksHardware StorNext File System Tuning Guide Network Configuration and Topology SwitchDistributed LAN Servers Distributed LAN Client Vs. Legacy Network Attached StoragePerformance Fault toleranceLoad Balancing Client Scalability Windows Memory Requirements Robustness and Stability Consistent Security ModelStorNext File System Tuning Windows Memory Requirements Sample FSM Configuration File StorNext File System Tuning Sample FSM Configuration File StorNext File System Tuning Sample FSM Configuration File StorNext File System Tuning Sample FSM Configuration File StorNext File System Tuning Sample FSM Configuration File StorNext File System Tuning Sample FSM Configuration File