adaptation-rule pir adaptation-rule
no adaptation-rule
config>qos>mc-mlppp>sap-egress>queue
This command is used to define how an operational rate is selected based on the configured PIR rate. Operational rates are the finite set of rates at which the schedulers on the network processor can operate.
The no form of the command removes any adaptation-rule constraints used to derive the operational rates for the policy. When a specific adaptation-rule is removed, the default constraints for rate apply.
closest
defines the constraints enforced when adapting the PIR rate defined within the queue queue-id rate command. The pir parameter requires a qualifier that defines the constraint used when deriving the operational PIR for the queue. When the rate command is not specified, the default applies.
specifies the constraints to be used while computing the operational PIR rate. The max (maximum), min (minimum), and closest parameters are mutually exclusive.
cbs {size-in-kbytes | default}
no cbs
config>qos>mc-mlppp>sap-egress>queue
This command overrides the default Committed Buffer Space (CBS) reserved buffers for the queue.
The value in kilobytes is converted automatically to the number of buffers. The conversion calculation uses a non-configurable buffer size of 2304 bytes or 512 bytes, depending on the type of adapter card. See Table: Buffer Support on Adapter Cards and Platforms for a list of adapter cards and their associated buffers. The calculation is:
Number of buffers = Configured CBS value in bytes / Buffer size in bytes
The no form of this command returns the CBS size to the default value.
‟default” (8 kbytes for adapter cards and platforms with 512 byte buffer size) (18 kbytes for adapter cards and platforms with 2304 byte buffer size)
this parameter is an integer expression of the number of kilobytes reserved for the queue. A value of 0 specifies that no reserved buffers are required by the queue (a minimal reserved size can still be applied for scheduling purposes).
returns the CBS size to the default value
high-prio-only percent
no high-prio-only
config>qos>mc-mlppp>sap-egress>queue
The high-prio-only command configures the percentage of buffer space for the queue, used exclusively by high-priority packets. The specified value overrides the default value for the context.
The priority of a packet can only be set in the service ingress policy and is only applicable on the ingress queues for a SAP. The profile state is used for enqueuing priority at sap-egress.
The no form of this command restores the default high-priority reserved size.
10 (percent)
the percentage reserved for high priority traffic on the queue
mbs size [bytes | kilobytes]
no mbs
config>qos>mc-mlppp>sap-egress>queue
This command sets the Maximum Burst Size (MBS) value for the buffers of the specific queue. The value is configured in bytes or kilobytes and overrides the default value for the context. The default configuration is in kilobytes.
The config>qos>mc-mlppp>sap-egress>info detail screen shows the MBS in terms of bytes, unless it is a multiple of 1000. In that case, the display shows the MBS in kilobytes. For example, entering mbs 200 or mbs 200 kilobytes configures and displays ‟200 kilobytes”, entering mbs 200000 bytes also configures and displays ‟200 kilobytes”, and entering mbs 200100 bytes configures and displays ‟200100 bytes”.
For the 7705 SAR, a 1 kbyte of buffer management space is 1000 bytes.
The MBS value in bytes is converted automatically to packets. The conversion calculation uses a non-user-configurable buffer size of 2304 bytes or 512 bytes, depending on the type of adapter card. See Table: Buffer Support on Adapter Cards and Platforms for a list of adapter cards and their associated buffers. The calculation is:
Number of buffers = Configured MBS value in bytes / Buffer size in bytes (2304 or 512)
The MBS value is used by a queue to determine whether it has exhausted all of its buffers while enqueuing packets. Once the queue has exceeded the amount of buffers allowed by MBS, all packets are discarded until packets have been drained from the queue.
The sum of the MBS for all queues on an adapter card can exceed the total amount of buffering available. Therefore, for a packet arriving at a queue that has not exceeded its MBS size, it is not guaranteed that a buffer will be available. If a buffer is not available, the packet will be discarded. RED/WRED slope parameters can be configured to control congestion in the case where the buffer capacity of the card is becoming exhausted.
Setting proper CBS parameters and controlling CBS oversubscription is one major safeguard against queue starvation (that is, when a queue does not receive its fair share of buffers). Another safeguard is to properly set the RED/WRED slope parameters for the needs of services on this port or channel.
The no form of this command returns the MBS size assigned to the queue to the default value.
180 (kbytes) (converted to 78 packets when buffer size is 2304 bytes and to 351 packets when buffer size is 512 bytes)
the size parameter is an integer expression of the maximum number of bytes of buffering allowed for the queue. A value of 4000 bytes or less causes the queue to discard all packets. Selecting default returns the MBS to the default value.
specifies that the size entered is in bytes
specifies that the size entered is in kbytes
rate pir-rate
no rate
config>qos>mc-mlppp>sap-egress>queue
This command defines the administrative PIR parameters for the queue. The PIR defines the maximum rate that the queue can transmit packets out an egress interface. Defining a PIR does not necessarily guarantee that the queue can transmit at the intended rate. The actual rate sustained by the queue can be limited by oversubscription factors or available egress bandwidth.
The rate command can be executed at any time, altering the PIR rates for all queues created through the association of the MC-MLPPP SAP egress policy with the queue-id.
The no form of the command returns all queues created with the queue-id by association with the QoS policy to the default PIR parameters (max).
max (this value specifies the amount of bandwidth in kb/s. The max value and the pir-rate value are mutually exclusive.)
defines the administrative PIR rate, in kb/s, for the queue. When the rate command is executed, a valid PIR setting must be explicitly defined. When the rate command has not been executed, the default PIR of max is assumed. Fractional values are not allowed and must be given as a positive integer. The PIR rate has a minimum value of 8kb/s.
The actual PIR rate is dependent on the queue’s adaptation-rule parameters and the actual hardware where the queue is provisioned.
slope-policy name
no slope-policy
config>qos>mc-mlppp>sap-egress queue
This command specifies the slope parameters controlling the queue.
The no form of this command reverts to the default value.
default
the name of the slope policy