MueLu: Static library is HUGE; splitting by GlobalOrdinal etc. won't help

Created by: mhoemmen

@trilinos/muelu @micahahoward @tcfisher

SPARC wasn't actually able to build MueLu before on Intel 17, static debug, because the library was too huge for the linker. PR #3100 fixes this for ATDM Dashboard builds by using a new BinUtils module, and thus a new linker. I fixed this for SPARC by setting Tpetra_INST_INT_INT=OFF and Amesos2_ENABLE_Epetra=OFF.

While I'm able to build Trilinos now, libmuelu.a is still 3.8G. This is with only one Scalar type (double), one GlobalOrdinal type (long long), and one Node type (OpenMP) enabled. That suggests that splitting MueLu's library by GlobalOrdinal and/or Node won't actually help shrink the library. Instead, if we want to split it, we'll need to split it by topic.

Expectations

Libraries shouldn't be so huge that they require 64-bit linkers.

Current Behavior

libmuelu.a is 3.8G when I have only one Scalar, GlobalOrdinal, and Node type combination enabled.

Possible Solution

Split libmuelu by topic, e.g., smoothers, aggregation, etc.

Steps to Reproduce

Intel 17 static debug build, ATDM libraries.

Related Issues

• Follows #3069 (closed)