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priority value buffer-size size pause-threshold threshold-value resume-
offset threshold-value shared-threshold-weight size
Dell(conf-dcb-buffer-thr)#priority 0 buffer-size 52 pause-threshold 16
resume-offset 10 shared-threshold-weight 7
priority
Syntax
priority value buffer-size size pause-threshold threshold-value resume-
offset threshold-value shared-threshold-weight size
Parameters
priority Specify the priority of the queue for which the buffer space settings apply
value Enter a number in the range of 0 to 7 to denote the priority that is allocated to the
dynamic buffer control mechanism
buffer-size Ingress buffer size
size Size of the ingress buffer in KB. Enter a number in the range from 0 to 7787. The
default is 45 KB.
pause-threshold Buffer limit for pause frames to be sent
threshold-value Buffer limit at which the port sends the pause to peer in KB. Enter a number in the
range from 0 to 7787. The default is 10 KB.
resume-offset Buffer offset limit for resuming in KB
threshold-value Buffer offset limit at which the port resumes the peer in KB. Enter a number in the
range from 1 to 7787. The default is 10 KB.
shared-
threshold-weight
Buffer shared threshold weight
size Weightage of the priorities on the shared buffer size in the system. Enter a number
in the range from 0 to 9. The default shared threshold weight is 10.
Default The default size of the ingress buffer is 45 KB. The default buffer limit at which the port sends the pause
to peer and recommences the sending of packets to the peer is 10 KB. The default threshold weight of
the shared buffer space is 10.
Command Modes DCB-BUFFER-THRESHOLD mode
Command
History
Version Description
9.7(0.0) Introduced on the Z9500.
Usage
Information
For each priority, you can specify the shared buffer threshold limit, the ingress buffer size, buffer limit for
pausing the acceptance of packets, and the buffer offset limit for resuming the acceptance of received
packets. When PFC detects congestion on a queue for a specified priority, it sends a pause frame for the
802.1p priority traffic to the transmitting device.
You can use theprioritycommand to set up both the administrative and peer-related PFC priorities.
For example, you can configure the intended buffer configuration for all eight priorities. If you configure
the number of lossless queues as 4 and if the administrator-configured priorities configured within the
DCB input policy is applied, then the configuration for those priorities are pre-designed. However, if the
peer-provided priorities are applied, although a DCB input policy is present, the peer-provided priorities
become effective for buffer configuration. This method of configuration provides an easy and flexible
technique to accommodate both administratively-configured and peer-configured priorities.
Example
Dell(conf-dcb-buffer-thr)#priority 0 buffer-size 52 pause-threshold 16
resume-offset 10 shared-threshold-weight 7
518 Data Center Bridging (DCB)