Re: [eigen] Status of non-OpenMP-based multithreading

[Rasmus Larsen <rmlarsen@xxxxxxxxxx>]

This is something that frustrates me as well. The tensor library has its own threadpool implementation and most operations are multi-threaded. In particular it provides a multi-threaded contraction, which is a super set of GEMM - Benoit Steiner can give more details. I would be in favor making this mechanism available to the rest of Eigen (maybe implement a simple ParallelFor mechanism on top of it for developers to use), such that we can provide multi-threading independent of OpenMP.  I'd be happy to help..

Rasmus

On Fri, Mar 4, 2016 at 11:33 AM, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:

Hi,

I keep running into Eigen users who can't get good multithreading, either because their toolchain doesn't support OpenMP, or because they run into performance bugs in their OpenMP implementation.

I would like to know what is the current status of non-OpenMP-based multithreading in Eigen?

In particular, does the Tensor module offer its own implementation of a multi-threaded GEMM? Can that be merged into Core?

Cheers,

Benoit