About Performance Buffers; Configuring Performance Buffers; About Extended Bb_Credits - HP Cisco MDS 9216 - Fabric Switch Configuration Manual

Chapter 20 Configuring Interfaces
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
Expand Switches > Interfaces and then select FC Physical. You see the interface configuration in the
Step 1
Information pane.
Choose the Bb Credit tab.
Step 2
You see the buffer credits.
Set any of the buffer-to-buffer credits for an interface.
Step 3
Click Apply Changes.
Step 4

About Performance Buffers

Note Performance buffers are not supported on the Cisco MDS 9124 Fabric Switch, the Cisco Fabric Switch
for HP c-Class BladeSystem, and the Cisco Fabric Switch for IBM BladeCeter.
Regardless of the configured receive BB_credit value, additional buffers, called performance buffers,
improve switch port performance. Instead of relying on the built-in switch algorithm, you can manually
configure the performance buffer value for specific applications (for example, forwarding frames over
FCIP interfaces).
For each physical Fibre Channel interface in any switch in the Cisco MDS 9000 Family, you can specify
the amount of performance buffers allocated in addition to the configured receive BB_credit value.
The default performance buffer value is 0. If you set the performance buffer value to 0, the built-in
algorithm is used. If you do not specify the performance buffer value, 0 is automatically used.

Configuring Performance Buffers

To configure performance buffers for a Fibre Channel interface using Fabric Manager, follow these
steps:
Step 1 Expand Switches > Interfaces and then select FC Physical.
You see the interface configuration in the Information pane.
Click the BB Credit tab
Step 2
You see performance buffer information in the columns Perf Bufs Admin and Perf Bufs Oper.
Set the performance buffers for an interface.
Step 3
Click Apply Changes.
Step 4

About Extended BB_credits

You can use the extended BB_credits flow control mechanism in addition to BB_credits for long haul
links.
This section includes the following topics:
OL-16184-01, Cisco MDS SAN-OS Release 3.x
Cisco MDS 9000 Family CLI Configuration Guide
Buffer Credits
20-21