Avaya P580 - Manual (Page 644)

20-6 Avaya P550R, P580, P880, and P882 Multiservice Switch User Guide, v5.3.1
Chapter
High Priority
Allocation Displays the percent of the buffer’s queuing space allotted
to high priority traffic. Because the high-priority queue is
serviced more frequently than the normal priority queue,
raising this value may not necessarily provide better
service. In fact, if you are using the high-priority queue
for delay-sensitive traffic, you may want to reduce the
amount of memory devoted to the high-priority queue.
This ensures that packets that cannot be delivered in a
timely manner are discarded. If you want the high
priority queue to guarantee delivery of as many packets
as possible, regardless of delay, increase this value. The
change does not take effect until you reset the switch.
Priority
Threshold Allows you to set this parameter to the value at which the
P550R switch starts sending packets to the high-priority
queue. The default value (4) causes all traffic with a
priority greater than or equal to 4 (4, 5, 6, and 7) to be
assigned to the high-priority queue. Priority schemes
have more than two queues (the IEEE allows up to 8,
numbered 0 through 7). Avaya recommends that you do
not change this parameter.
High Priority
Service Ratio Allows you to set how many times the high priority
queue is serviced for each time the low priority queue is
serviced. The ideal value changes from queue to queue,
but the goal is to ensure that traffic mix guarantees
optimal mix between high-priority and best effort traffic.
High and
Normal
Overflow
Drops Displays the number of packets dropped because the
associated buffer is full. Indicates that the device
immediately before the queue is processing traffic faster
than the next downstream element can process the same
volume of traffic. For example, overflow drops on the
input buffer indicate that traffic is arriving faster than the
switch matrix can process it. Overflow drops on the
output buffers indicates that the output port cannot
handle the volume of the load being offered.
High and
Normal Stale
Drops Displays the number of packets dropped because they
timed out waiting for service (using the age timer value).
In the high-priority queue, this can help determine how
efficiently the switch is processing “better never than
late” traffic. Excessive stale drops on the high-priority
queue may indicate the need to increase the service ratio
on the high-priority queue.
Congestion
Drops Displays the number of packets dropped because the
switch controller has sensed congestion at the outbound
port.
Table 6-136. Buffer Detail Configuration Dialog Box
Parameter Definition ...