UCX and MPI one-sided in v4.1.0

[jsquyres]

From https://www.mail-archive.com/users@lists.open-mpi.org/msg34261.html:

Why does 4.1 still not use the right defaults with UCX?

Without specifying osc=ucx, IMB-RMA crashes like 4.0.5. I haven't checked what else it is UCX says you must set for openmpi to avoid memory corruption, at least, but I guess that won't be right either. Users surely shouldn't have to explore notes for a fundamental library to be able to run even IMB.

FYI @loveshack

[hoopoepg]

Hi

I tried to send e-mail to original thread, but it was rejected... So, duplicate it here:

Thank you for bug report.

Could you describe your system:

• What OS is used? How OMPI/UCX were installed
• Is your application launched on single node or multiple nodes were used
• What is command line?
• Could you also provide output from commands:

ompi_info --version
ucx_info -v
ucx_info -pwe -D net -u t
ucx_info -pwe -D net -u r
ucx_info -pwe -D shm -u t
ucx_info -pwe -D shm -u r
ucx_info -d

Thank you

[loveshack]

The problem is #8102. However, I mis-remembered that osc=ucx came from the ucx doc, apologies. That just says you must avoid the uct btl, which OMPI 4.1 still builds and uses. I realize that with btl ^uct, at least that failure goes away.

[bosilca]

The UCT BTL is only built with a version of UCX prior to 1.9. What version of UCX are you using here ?

[jsquyres]

@loveshack Can you reply? Thanks!

[loveshack]

See my reply in #8102