That seemed to fix the issue.

Thanks!

Bruce

From: Zhou, Hui <zhouh@anl.gov>
Date: Thursday, October 3, 2024 at 11:01 AM
To: discuss@mpich.org <discuss@mpich.org>
Cc: Palmer, Bruce J <Bruce.Palmer@pnnl.gov>
Subject: Re: Maximum number of communicators

Hi Bruce,

Try configure mpich using --with-device=ch4:ofi --enable-extended-context-bits.

Hui

From: Palmer, Bruce J via discuss <discuss@mpich.org>
Sent: Thursday, October 3, 2024 11:44 AM
To: discuss@mpich.org <discuss@mpich.org>
Cc: Palmer, Bruce J <Bruce.Palmer@pnnl.gov>
Subject: [mpich-discuss] Maximum number of communicators

Hi, I’m looking at using MPI RMA to support sparse data structures in Global Arrays. I’ve got an application that uses a large number of sparse arrays and it is failing when the number of sparse arrays reaches about 500. Each sparse array is

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Hi,

I’m looking at using MPI RMA to support sparse data structures in Global Arrays. I’ve got an application that uses a large number of sparse arrays and it is failing when the number of sparse arrays reaches about 500. Each sparse array is built on top of 4 conventional global arrays and each global array uses one MPI Window. Each Window appears to be creating its own communicator and I’m hitting an internal limit at 2048 communicators. Is there a way to increase the number of communicators?

Bruce Palmer