follow dev55, I plan to implement a preliminary multi-threaded PyTorch version of mg in dev56 (with the finest level of matvec being parallel, and the rest being on the root thread, using mpi4py), however, I encountered a bug in the early testing of the multi-threaded PyTorch version of bistabcg(referring to PyQCU/test/bug24.log), hope to be able to successfully eliminate the bug later. orz