bitromortac 75a9dc9103 routing: limit capacity factor and tune parameters ...

* The maximal reduction in the probability is limited to 0.5 (previously
  ~0.05), such that we don't get too low apriori probabilities.
  Otherwise, this may lead to a too strong selection of large (and maybe
  expensive) channels. A two-hop path would get total probability
  penalties of:

  - 1000PPM/(0.6*0.6) = 2778 PPM in the unsaturated case
  - 1000PPM/(0.6*(0.6*0.5)) = 5556 PPM in the saturated case, where the
    second hop is saturated

  The difference in PPM of 2778 PPM should be enough to bias towards the
  first path.

* The smearing factor is reduced. Previously we had to keep a higher
  smearing factor in order to make the capacity factor not go to zero
  for high amounts, to still give a fully saturated channel a chance.
  This is not needed anymore due to the capping to 0.5. A lower value of
  the smearing factor lets us more precisely choose a capacity fraction
  and the capacity factor is more neutral when it comes to intermediate
  amounts.

We set a conservative default value for the capacity fraction, which
still has the effect of discarding exhausted channels, giving a
noticeable effect when about 90% of the capacity is being used.

2023-02-24 15:28:55 +01:00

8.8 KiB

Raw Blame History

View Raw