| Description | The maximum shaping delay in milliseconds. That is, the maximum
amount of time for which the HE will allow buffering of any
rate exceeded flow. If the max buffering delay is large,
then grants/packets of the flow will be buffered for a
longer period of time even though the flow is rate exceeded.
This means fewer chances of drops for such rate exceeded
flow. However, too large a max shaping delay can result in
quick drainage of packet buffers at the HE, since several
packets will be in the shaping (delay) queue waiting for
their proper transmission time. Another important point to
note is that delaying a flow's packets (especially TCP
flows) for extended periods of time may be counter-
productive, since the higher protocol layers may assume
a packet loss after a certain amount of time.
The maximum shaping delay is only applied to rate limit
algorithm: Token bucket algorithm with shaping. If the rate
limit algorithm is not Token bucket algorithm with shaping,
the value is always na(1) which is not applicable. In this
case, you will be allowed to set the value to na(1) only.
If the token count is less than the size of request/packet, HE
computes the shaping delay time after which the deficit number of
tokens would be available. If the shaping delay time is greater
than the maximum shaping delay, the request/packet will be
dropped.
The enumerations for cwdxQosIfRateLimitShpMaxDelay are:
na(1): maximum shaping delay is not applied to the current
rate limit algorithm
msec128(2): maximum shaping delay is 128 milliseconds
msec256(3): maximum shaping delay is 256 milliseconds
msec512(4): maximum shaping delay is 512 milliseconds
msec1024(5): maximum shaping delay is 1024 milliseconds
At the downstream, cwdxQosIfRateLimitShpMaxDelay
is configurable and the default value is msec128(2).
Whenever the downstream rate limit algorithm is changed
to Token bucket algorithm with shaping from other rate
limit algorithm, the value will be reset to the default
value.
At the upstream, cwdxQosIfRateLimitShpMaxDelay is not
configurable and it is read-only value. |