Fabric OS Reference Manual

46 Fabric OS Reference Manual
Virtual Channel Settings
The switch provides the ability to tune it in a specific application, by
configuring the parameters for its eight virtual channels. Note that the first
two virtual channels are reserved for switch internal functions and are not
user-configurable.
The default virtual channel settings have already been optimized for switch
performance. Changing the default values can improve switch
performance, but it can also degrade performance. Do not change these
settings without fully understanding the effects of the changes.
Here are descriptions of the Virtual Channel Setting fields:
VC Link Control Specifies the virtual channel used for
N_Port
-generated, Class 2 link control frames (
ACK
s,
P_BSY
s,
P_RJT
s). Forces
N_Port
-generated link
control frames to be sent using a Class 2 data Virtual
Channel when set to 0. When set to 1, the control
frames are sent using a Virtual Channel normally
reserved for fabric-internal traffic. This setting is
configurable only when VC Encoded Address Mode
is set.
Table 2. Virtual Channel Settings
Field Type Default Range
VC Link Control
Number 0 0 to 1
VC Class 2
Number 2 2 to 5
VC Class 3
Number 3 2 to 5
VC Multicast
Number 7 6 to 7
VC Priority 2
Number 2 2 to 3
VC Priority 3
Number 2 2 to 3
VC Priority 4
Number 2 2 to 3
VC Priority 5
Number 2 2 to 3
VC Priority 6
Number 3 2 to 3
VC Priority 7
Number 3 2 to 3