JESS: On the Performance of Logical Retractions

Hi,

I am doing some experiments with a set of rules which contain the "logical"
CE.
I intend to see the performance of Jess on a set of assertions as well as
retractions.

After some experiments, I found that the runtime for assertions is much less
than that of retractions.
In fact, the performance on retractions is so bad that I would rather re
(run) jess on a retracted kb.


A sample test case:
The KB size,  number of assertions, number of retractions, and number of
rules are 100K, 50K, 1k, and 100, respectively.
runtimes are >> initial run: 860ms,  assertions:320ms --  retractions: 4s.


Would you please give some hints on the reason?


Thanks in advance.
--Oli.