Load Balancing Policies; Configuring Multipathing - IBM SYSTEM STORAGE DS3000 Installation Manual

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
Digital Media Storage Solution Installation Guide
© Copyright 2010, IBM Corporation. All rights reserved.
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