IBM DS4000 Computer Hardware User Manual


 
Digital Media Storage Solution Installation Guide 26
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Detailed Statistics Info
Statistics (Shown in Average and Total)
Read Rate / Data Read Read count in bytes for a particular path
Write Rate / Data Written Write count in bytes for a particular path
Command Rate / Command Count Number of commands sent down a particular path
Error Rate / Error Count Number of errors for a particular path
Load Balancing Policies
Pressure
The path with the fewest bytes will be used
This option provides the best performance for the digital video market (large transfers)
Queue Depth
The path with the fewest commands will be used
Round Robin
The least used path is selected
Configuring Multipathing
When new devices (Targets and LUNs) are presented to the ATTO HBA, multipathing must be configured
and/or saved using the the ATTO Configuration Tool.
User’s can choose between default settings or custom settings (Load Balancing Policies).
Default Settings for DS Storage
Devices are configured using the following policies:
Read/Write modes will be set automatically
Load Balancing Policy for all targets, LUN’s and paths is set to Pressure
Saving Default Settings
Navigate to the Paths tab in the Apple toolbar
Choose “Save Configuration”
Custom Settings
Load Balancing can be configured on a per LUN or per Target basis (depending on which is highlighted in
the left pane)
If the Target is highlighted, then all LUN‟s controlled by it will be configured the same.
Highlight either the Taget or LUN to be configured
Navigate to the Paths tab in the Apple toolbar
Choose “Load Balancing”
Notice the configurable options in the lower right pane
Select the Load Balancing Policy for the highlighted path