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space to be allocated for each priority and the pause or resume thresholds for the buffer. This method of
configuration enables you to effectively manage and administer the behavior of lossless queues.
Example
DellEMC(conf-if-te-1/1/1/1)# dcb-policy buffer-threshold test
dcb pfc-total-buffer-size
Configure the total buffer size for PFC in kilobytes.
Syntax
dcb pfc-total—buffer—size buffer-size
Parameters
buffer-size Enter a number in the range of 0 to 3399.
Default The default is 2656KB.
Command Modes CONFIGURATION mode
Command
History
This guide is platform-specific. For command information about other platforms, see the relevant Dell EMC
Networking OS Command Line Reference Guide.
Version Description
9.11(2.0P0) Default value is changed from 3088 KB to 2656 KB in the Z9100-ON and S6100-ON.
9.10(0.1) Introduced on the S6010-ON and S4048T-ON.
9.10(0.0) Introduced on the S6100.
9.8(1.0) Introduced on the Z9100–ON.
9.8(0.0P5) Introduced on the S4048–ON.
9.7(0.0) Introduced on the S6000-ON.
9.6(0.0) Introduced on the S5000.
9.3(0.0) Introduced on the S6000, S4810, and S4820T.
Usage
Information
Configure the maximum buffer available for PFC traffic. You can choose to increase or decrease the buffer size that
is allocated in the system by default. However, if you modify the PFC buffer size lower than the previously configured
size, the system determines whether this reduction in size is valid without disrupting the existing configuration. In
such a scenario, disable and re-enable DCB.
The lossless queue limit per port is validated based on the dcb pfc-queues command. PFC queue configuration
identifies the maximum number of queues a port can support. Although the queue limit per port is a baseline when
dynamic buffering is enabled, the limit per port for queues depends on the availability of the buffer.
Example
DellEMC(conf)#dcb pfc-total-buffer-size 2800
DellEMC(conf)#
DellEMC#show dcb
DCB Status: Enabled, PFC Queue Count: 2
Total Buffer: Total available buffer excluding the buffer pre-allocated
for guaranteed services like global headroom, queue's min
guaranteed buffer and CPU queues.
PFC Total Buffer: Maximum buffer available for lossless queues.
PFC Shared Buffer: Buffer used by ingress priority groups for shared usage.
PFC Headroom Buffer: Buffer used by ingress priority group for shared headroom usage.
PFC Available Buffer: Current buffer available for new lossless queues to be
Provisioned.
stack-unit Total Buffer PFC Total Buffer PFC Shared Buffer PFC Headroom Buffer PFC Available Buffer
PP (KB) (KB) (KB) (KB) (KB)
-----------------------------------------------------------------------------------------------------
1 0.0 3399 2800 1040 1040 711
1 0.1 3399 2800 1040 1040 720
1 0.2 3399 2800 1040 1040 711
500 Data Center Bridging (DCB)