Hi Niyaz,

The triplet meanings are (start node id, number of nodes, processes per node), and processes are assigned round-robin fashion. So "(0, 2, 1)"  with 2 processes on 2 nodes expands into "0, 1" - first process on node 0 and 2nd process on node 1.

Hope that helps.

--
Hui
From: Niyaz Murshed via discuss <discuss@mpich.org>
Sent: Wednesday, August 7, 2024 12:18 PM
To: discuss@mpich.org <discuss@mpich.org>
Cc: Niyaz Murshed <Niyaz.Murshed@arm.com>; nd <nd@arm.com>
Subject: [mpich-discuss] How to read --pmi-process-mapping
 
Hello, I am launching 2 processes on 2 nodes. The processes get rank 0 and 1 --version 4. 3. 0a1 --iface-ip-env-name PMI_HOSTNAME --hostname 192. 168. 2. 100 --global-core-map 0,1,2 --pmi-id-map 0,0 --global-process-count 2 --auto-cleanup 1 --pmi-kvsname
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Hello,

 

I am launching 2 processes on 2 nodes. The processes get rank 0 and 1

 

--version 4.3.0a1 --iface-ip-env-name PMI_HOSTNAME --hostname 192.168.2.100 --global-core-map 0,1,2 --pmi-id-map 0,0 --global-process-count 2 --auto-cleanup 1 --pmi-kvsname kvs_31321_0_150440369_ampere-altra-2-1 --pmi-process-mapping (vector,(0,2,1))

 

I see once rankmap is generated, its converted to a string “(vector,(0,2,1))”.

How do we read this  as?

 

Regards,

Niyaz