  In this paper, we show that with the state-of-art module intersection IBP
reduction method and our improved Leinartas' algorithm, IBP relations for very
complicated Feynman integrals can be solved and the analytic reduction
coefficients can be dramatically simplified. We develop a large scale parallel
implementation of our improved Leinartas' algorithm, based on the
\textsc{Singular}/\textsc{GPI-Space} framework. We demonstrate our method by
the reduction of two-loop five-point Feynman integrals with degree-five
numerators, with a simple and sparse IBP system. The analytic reduction result
is then greatly simplified by our improved Leinartas' algorithm to a usable
form, with a compression ratio of two order of magnitudes. We further discover
that the compression ratio increases with the complexity of the Feynman
integrals.
