Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual page 485

Chapter 22 Configuring Generation 2 and Generation 3 Switching Modules
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
The 48-Port and 24-Port 8-Gbps modules have dual global buffer pools. Each buffer pool in the 48-port
Note
modules support 24 ports and in the 24-port modules each buffer pool supports 12 ports.
Figure 22-3
cards).
Figure 22-3
Figure 22-4
The minimum BB_credits required to bring up a port is two buffers.
Figure 22-4
250 BB credits
OL-17256-03, Cisco MDS NX-OS Release 4.x
shows the allocation of BB_credit buffers on linecards (24-port and 48-port 4-Gbps line
Receive Buffers for Fibre Channel Ports in a Global Buffer Pool
Reserved Internal Buffers (not user configurable)
Performance Buffers (Shared Pool)
Common unallocated buffer pool for BB_credits
1 2 3
for each front panel FC ports
shows the default BB_credit buffer allocation model for 48-port 8-Gbps switching modules.
BB_Credit Buffer Allocation in 48-port 8-Gbps Switching Modules
All ports
shared (8 Gpbs)
32 BB credits
Dedicated
1 Gbps 2 Gbps
250 BB credits
Allocated BB_credit buffers
48-port module
Mixed
32 BB credits
4 Gbps
250 BB credits
Cisco MDS 9000 Family Fabric Manager Configuration Guide
Buffer Credit Allocation
N
All ports
dedicated (2 Gbps)
250 BB credits
Shared
8 Gbps
250 BB credits
22-11