lpEngArcTxCellThreshTable
1.3.6.1.4.1.562.2.4.1.12.23.5.440
This attribute is a vector which indicates the size and three discard
thresholds for transmit cell memory for this FP. The transmit cell
memory is used for storing ATM cells to be transmitted by this FP.
The first value indicates the transmit cell memory size. This is
derived based on the total transmit memory capacity of this FP, and
the value of the connectionPoolCapacity and the
txCellMemoryAllocation attributes.
The current value of txCellMemoryUsage together with the vector
of values in txCellMemoryThresholds determines the
txCellMemoryCongestionState. The congestion state determines
whether cells of a given discard priority (DP) are discarded or
queued for transmit.
When the txCellMemoryUsage attribute is between threshold 0 and
threshold 1, the txCellMemoryCongestionState indicates the value
0. In congestion state 0, traffic with DP > 0 is discarded. Threshold
1 is set approximately at 90 percent of threshold 0, the total transmit
cell memory size.
When the txCellMemoryUsage attribute is between threshold 1 and
threshold 2, the txCellMemoryCongestionState indicates the value
1. In congestion state 1, traffic with DP > 1 is discarded. Threshold
2 is set approximately at 85 percent of threshold 0, the total transmit
cell memory size.
When the txCellMemoryUsage attribute is between threshold 2 and
threshold 3, the txCellMemoryCongestionState indicates the value
2. In congestion state 2, traffic with DP > 2 is discarded. Threshold
3 is set approximately at 75 percent of threshold 0, the total transmit
cell memory size.
When the txCellMemoryUsage attribute is below threshold 3, the
txCellMemoryCongestionState indicates the value 3. In congestion
state 3, traffic with DP=3 is queued.