pytorch

6fb6dc42 - Improve heuristics for linalg_lu_solve when B is a matrix (#79838)

Improve heuristics for linalg_lu_solve when B is a matrix (#79838) When linalg_lu_solve was added in https://github.com/pytorch/pytorch/pull/72935 I made the big mistake of assuming that the choice of backend would not depend on number of columns of B. This turned out to be false by a large margin. This PR amends this and provides a heuristic that takes the number of columns of B into account. The heuristic is not simple and it was crafted by hand, but as the results show, it is effective. @xwang233 the cusolver team should look into this one, as I was able to outperform both cublas and cusolvers algorithms by using triangular solves... The benchmarks for the heuristics are here: https://github.com/pytorch/pytorch/pull/79838#issuecomment-1163802792 Pull Request resolved: https://github.com/pytorch/pytorch/pull/79838 Approved by: https://github.com/IvanYashchuk, https://github.com/albanD