Configuration Guide User guide

FastIron Configuration Guide 587
53-1002494-02
Dynamic buffer allocation for QoS priorities for FastIron X Series devices
Removing buffer allocation limits on
FastIron X Series devices
You can remove buffer allocation limits on all ports and all Traffic Classes globally. This permits all
available buffers in a port region to be used in a first-come-first-serve basis by any of its ports,
regardless of priority. This can be done using the following command.
Brocade(config)#buffer-sharing-full
Syntax: [no] buffer-sharing-full
The buffer-sharing-full command sets the total transmit queue depth limit and the transmit queue
depth limits for each Traffic Class to 4095 for all ports of the device. The command overrides any
existing individually configured queue depth limits.
ATTENTION
The buffer-sharing-full command should be used carefully. By entering this command, there is no
limit on the number of buffers a port or a specific priority on a port can use. One port could
potentially use up all the available buffers of its port region and cause starvation on other ports of
the port region.
Buffer profile configuration
The following Interface modules support up to eight buffer profiles:
• SX-FI48GPP
• SX-FI-24GPP
• SX-FI-24HF
• SX-FI-2XG
• SX-FI-8XG
A buffer profile defines the total transmit queue depth limit for a port and the transmit queue depth
limit for a given traffic class. On the listed supported Interface modules, each port is associated
with a buffer profile. In contrast, Interface modules other than the SX-FI-48GPP, SX-FI-24GPP,
SX-FI24-HF, SX-FI-2XG, and the SX-FI-8XG support the configuration of transmit queue depth limits
per port.
By default, each port on an SX-FI48GPP, SX-FI-24GPP, SX-FI-24HF, SX-FI-2XG or SX-FI-8XG Interface
module is associated with buffer profile ID 1. Profile 0 is reserved for buffer sharing. Default queue
depth limits are provided in “Default queue depth limits for FastIron X Series devices” on page 585.
To change the queue depth limit for a port on the supported Interface modules, configure a buffer
profile ID that is different from the default or configured value, and apply the buffer profile to the
port. When you change the queue depth limit on a port, the configuration will apply to all ports
associated with the same buffer profile ID. For example, if ports 1/1 through 1/5 are associated
with buffer profile ID 3 and you enter the qd 1/1 1000 command, the queue depth limit of 1000
will apply to ports 1/1 through 1/5.
NOTE
In the case of SX-FI48GPP module, the queue depth configured using the qd command is not
applicable when the port is set to speeds lower than 1Gbps. The qd command is applicable only
when the port is set to speeds greater than 1Gbps.