Configuration Guide User guide

FastIron Configuration Guide 1991

53-1002494-02

Scheduling QoS information

Bandwidth allocations of the hybrid WRR and SP queues

NOTE

On the SX-FI48GPP interface module, the bandwidth percentages for 8 to 4 queue mapping for

hybrid WRR and SP queues are different from other Brocade SX modules. For more information on

8 to 4 queue mapping on the SX-FI48GPP interface module, refer to “Default scheduling

configuration for the SX-FI48GPP module” on page 1985.

To change the default bandwidth percentages for the queues when the device is configured to use

the combined SP and WRR queuing mechanism, enter commands such as the following. Note that

this example uses the default queue names.

Brocade(config)#qos profile qosp7 sp qosp6 sp qosp5 20 qosp4 16 qosp3 16 qosp2 16

qosp1 16 qosp0 16

Syntax: [no] qos profile <queue 7> sp <queue 6> sp | <percentage> <queue 5> <percentage>

Each <queue> specifies the name of a queue, such as 7, 6, 5, 4, 3, 2, 1, and 0. You can specify the

queues in any order on the command line, but you must specify each queue. Note that queue 7

supports Strict Priority (sp) only, queue 6 supports both SP and WRR queuing mechanisms (sp |),

and queues 0 through 5 support the WRR queuing mechanism only.

NOTE

Brocade stackable devices that are operating as members of a stack reserve queue 7 for stacking

functions.

The sp parameter configures strict priority as the queuing mechanism. Note that only queue 7 and

queue 6 support this method.

The <percentage> variable configures WRR as the queuing mechanism and specifies the

percentage of the device outbound bandwidth allocated to the queue. The queues require a

minimum bandwidth percentage of 3 percent for each priority. When jumbo frames are enabled,

the minimum bandwidth requirement is 8 percent. If these minimum values are not met, QoS may

not be accurate.

NOTE

The percentages must add up to 100. The Brocade FastIron devices do not adjust the bandwidth

percentages you enter. In contrast, the BigIron QoS does adjust the bandwidth percentages to

ensure that each queue has at least its required minimum bandwidth percentage.