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10–NIC Partitioning and Bandwidth Management
Configuration Parameters
154 83840-546-00 E
Flow Control
The flow control setting of the port.
Physical Link Speed
The physical link speed of the port, either 1G or 10G.
Relative Bandwidth Weight (%)

The relative bandwidth setting represents a weight or importance of a
particular function. There are up to four functions per port. The weight is
used to arbitrate between the functions in the event of congestion.

The sum of all weights for the functions on a single physical port should be
either
0 or 100 .

A value of 0 for all functions means that each function transmits at 25% of
the physical link speed, not to exceed the Maximum Bandwidth setting
5
.

A value for a function between 1 and 100 represents a percentage of the
physical link speed and is used by an internal arbitration logic as an input
value (weight). A higher value causes this function to transmit relatively
more data, compared to a function (on the same port) that has defined a
lower value.

The smallest recommended value for a partition is 10.
Maximum Bandwidth (%)

The maximum bandwidth setting defines an upper threshold value, ensuring
that this limit is not exceeded during transmission. The valid range for this
value is between 1 and 100. The maximum bandwidth value is defined as a
percentage of the physical link speed.

It is possible for the sum of all maximum bandwidth values across the four
functions of a single port to exceed the physical link speed value of either
10Gbps or 1Gbps. This case is called oversubscription. In a case where
oversubscription congestion occurs on transmit, the
Relative Bandwidth
Weight value comes into effect.

The Maximum Bandwidth setting is only valid in the context of Tx, but not
Rx.
An example configuration:
Four functions (or partitions) are configured with a total of six protocols, as shown
below.
5
A Relative Bandwidth Weight value of “0” for all functions (or partitions) causes the bandwidth
allocation to be divided equally among all enabled offloads. A Relative Bandwidth Weight value
of “25” for all functions causes bandwidth allocation to be divided equally among all functions.
Please refer to the example below for distinction.