Hi Tengfei,
Related to MAX_NUMCELLS, LIM_NUMCELLSUSED_HIGH and LIM_NUMCELLSUSED_LOW
need to be revisited.
In Section 5.1., these values are used in the following way:
The counters are used as follows:
1. Both NumCellsElapsed and NumCellsUsed are initialized to 0 when
the node boots.
2. When the value of NumCellsElapsed reaches MAX_NUMCELLS:
* If NumCellsUsed > LIM_NUMCELLSUSED_HIGH, trigger 6P to add a
single cell to the preferred parent
* If NumCellsUsed < LIM_NUMCELLSUSED_LOW, trigger 6P to remove a
single cell to the preferred parent
* Reset both NumCellsElapsed and NumCellsUsed to 0 and go to
step 2.
NumCellUsed should have an integer value which is equal to or greater
than 0. Then, LIM_NUMCELLSUSED_HIGH and LIM_NUMCELLSUSED_LOW should be
the same type of value. However, these recommended values are expressed
in percentage, which cannot be compared directly with NumCellsUsed.
Figure 2 lists MSF Constants and their RECOMMENDED values.
+------------------------------+-------------------+
| Name | RECOMMENDED value |
+------------------------------+-------------------+
| NUM_CH_OFFSET | 16 |
| KA_PERIOD | 1 min |
| LIM_NUMCELLSUSED_HIGH | 75 % |
| LIM_NUMCELLSUSED_LOW | 25 % |
A correction would be either replacing NumCellsUsed in Section 5.1 with
(NumCellsUsed / NumCellsElapse), or removing '%' in Figure 2 with
changing the recommended values to something which can work with a
recommended value of MAX_NUMCELLS.
On 11/27/2019 9:05 PM, Tengfei Chang wrote:
By the way, the default or recommended value of MAX_NUMCELLS is 8?
MAX_NUMCELLS is not listed in Figure 3.
TC: 8 is just a value in the example, not recommended. For periodic
traffic, or traffic load changes slowly, a larger MAX_NUMCELLS is preferred.
Some proposal for the recommended value of MAX_NUMCELLS: 64 (power of
2), or 100.
Best,
Yatch
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