Quantum 3.1.4.1 manual ForcestripeAlignment, FsBlockSize

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StorNext File System Tuning

The Metadata Controller System

Example: ThreadPoolSize 32

# default 16, 512 KB memory per

thread

 

ForcestripeAlignment

This setting should always be set to Yes. This is critical if the largest StripeBreadth defined is greater than 1MB. Note that this setting is not adjustable after initial file system creation.

Example: ForcestripeAlignment

Yes

FsBlockSize

The FsBlockSize (FSB), metadata disk size, and JournalSize settings all work together. For example, the FsBlockSize must be set correctly in order for the metadata sizing to be correct. JournalSize is also dependent on the FsBlockSize.

For FsBlockSize the optimal settings for both performance and space utilization are in the range of 16K or 64K.Settings greater than 64K are not recommended because performance will be adversely impacted due to inefficient metadata I/O operations. Values less than 16K are not recommended in most scenarios because startup and failover time may be adversely impacted. Setting FsBlockSize to higher values is important for multiterabyte file systems for optimal startup and failover time.

Note: This is particularly true for slow CPU clock speed metadata servers such as Sparc. However, values greater than 16K can severely consume metadata space in cases where the file-to- directory ratio is low (e.g. less than 100 to 1).

For metadata disk size, you must have a minimum of 25 GB, with more space allocated depending on the number of files per directory and the size of your file system.

The following table shows suggested FsBlockSize (FSB) settings and metadata disk space based on the average number of files per directory and file system size. The amount of disk space listed for metadata is in addition to the 25 GB minimum amount. Use this table to determine the setting for your configuration.

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Contents StorNext Copyright Statement Contents Contents Underlying Storage System StorNext File System TuningCaching RAID Cache ConfigurationRAID Write-Back RAID Read-Ahead RAID Level, Segment Size, and Stripe Size File Size Mix and Application I/O Characteristics NFS / Cifs Buffer CacheMetadata Network Snfs and Virus CheckingMetadata Controller System Stripe Groups FSM Configuration File SettingsAffinities StripeBreadth ThreadPoolSize BufferCacheSizeInodeCacheSize FsBlockSize ForcestripeAlignmentFsBlockSize JournalSize JournalSizeSnfs Tools StorNext File System Tuning Metadata Controller System StorNext File System Tuning Metadata Controller System Latency-testindex-number seconds Mount Command Options Hardware Distributed LAN Disk Proxy NetworksSnfs External API StorNext File System Tuning Guide Switch Network Configuration and TopologyDistributed LAN Client Vs. Legacy Network Attached Storage Distributed LAN ServersLoad Balancing Client Scalability Fault tolerancePerformance Robustness and Stability Consistent Security Model Windows Memory RequirementsStorNext 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