From 504109236dd1295eb40ca723e4024ebe04553125 Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 15:08:24 +0100
Subject: [PATCH 01/13] template mpi.conf

---
 tasks/runtime.yml | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tasks/runtime.yml b/tasks/runtime.yml
index 5edd5fc0..0147cb24 100644
--- a/tasks/runtime.yml
+++ b/tasks/runtime.yml
@@ -103,6 +103,20 @@
   register: ohpc_cgroup_conf
   # NB uses restart rather than reload as this is needed in some cases
 
+- name: Template mpi.conf
+  template:
+    src: "{{ openhpc_mpi_template }}"
+    dest: "{{ openhpc_slurm_conf_path | dirname }}/mpi.conf"
+    owner: root
+    group: root
+    mode: "0644"
+  when:
+    - openhpc_enable.control | default(false)
+    - openhpc_mpi_conf | length > 0
+  notify:
+    - Restart slurmctld service
+  register: ohpc_mpi_conf
+
 # Workaround for https://bugs.rockylinux.org/view.php?id=10165
 - name: Fix permissions on /etc for Munge service
   ansible.builtin.file:

From 4996f54857b8651b1ec301c4a6f652fcf0a8d7b1 Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 15:13:29 +0100
Subject: [PATCH 02/13] Update main.yml

---
 defaults/main.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/defaults/main.yml b/defaults/main.yml
index 8f597ec3..5bbb1ab6 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -55,6 +55,7 @@ openhpc_state_save_location: /var/spool/slurm
 openhpc_slurmd_spool_dir: /var/spool/slurm
 openhpc_slurm_conf_path: /etc/slurm/slurm.conf
 openhpc_slurm_conf_template: slurm.conf.j2
+openhpc_mpi_conf_template: mpi.conf.j2
 
 # Accounting
 openhpc_slurm_accounting_storage_host: "{{ openhpc_slurmdbd_host }}"

From 154683810b88c376d376b17b5fc90179ae18d74c Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 15:14:59 +0100
Subject: [PATCH 03/13] Update main.yml

---
 defaults/main.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/defaults/main.yml b/defaults/main.yml
index 5bbb1ab6..4a88d3df 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -50,12 +50,12 @@ openhpc_config: {}
 openhpc_cgroup_config: {}
 openhpc_gres_template: gres.conf.j2
 openhpc_cgroup_template: cgroup.conf.j2
+openhpc_mpi_template: mpi.conf.j2
 
 openhpc_state_save_location: /var/spool/slurm
 openhpc_slurmd_spool_dir: /var/spool/slurm
 openhpc_slurm_conf_path: /etc/slurm/slurm.conf
 openhpc_slurm_conf_template: slurm.conf.j2
-openhpc_mpi_conf_template: mpi.conf.j2
 
 # Accounting
 openhpc_slurm_accounting_storage_host: "{{ openhpc_slurmdbd_host }}"

From 7572bb2fbad173f58992ea618c4bcfa6d4a1233a Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 15:16:17 +0100
Subject: [PATCH 04/13] Create mpi.conf.j2

---
 templates/mpi.conf.j2 | 4 ++++
 1 file changed, 4 insertions(+)
 create mode 100644 templates/mpi.conf.j2

diff --git a/templates/mpi.conf.j2 b/templates/mpi.conf.j2
new file mode 100644
index 00000000..d212c759
--- /dev/null
+++ b/templates/mpi.conf.j2
@@ -0,0 +1,4 @@
+# {{ ansible_managed }}
+{% for line in openhpc_mpi_conf %}
+{{ line }}
+{% endfor %}

From b2367a7864be5837fa2791a6694f3506b7fab90a Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 15:19:17 +0100
Subject: [PATCH 05/13] empty default mpi conf

---
 defaults/main.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/defaults/main.yml b/defaults/main.yml
index 4a88d3df..5ba72e16 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -51,6 +51,7 @@ openhpc_cgroup_config: {}
 openhpc_gres_template: gres.conf.j2
 openhpc_cgroup_template: cgroup.conf.j2
 openhpc_mpi_template: mpi.conf.j2
+openhpc_mpi_conf: []
 
 openhpc_state_save_location: /var/spool/slurm
 openhpc_slurmd_spool_dir: /var/spool/slurm

From 72cc226d209e8879b90af2d1f04b8789941e668f Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 16:53:30 +0100
Subject: [PATCH 06/13] notify slurmd restart handler for mpi.conf changes

---
 tasks/runtime.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tasks/runtime.yml b/tasks/runtime.yml
index 0147cb24..b4607482 100644
--- a/tasks/runtime.yml
+++ b/tasks/runtime.yml
@@ -148,6 +148,7 @@
   when:
     - openhpc_slurm_control_host in ansible_play_hosts
     - hostvars[openhpc_slurm_control_host].ohpc_slurm_conf.changed or
+      hostvars[openhpc_slurm_control_host].ohpc_mpi_conf.changed or
       hostvars[openhpc_slurm_control_host].ohpc_cgroup_conf.changed or
       hostvars[openhpc_slurm_control_host].ohpc_gres_conf.changed # noqa no-handler
   notify:

From 355dd0a9d1ccd6fb7930c6dc149d6c5fcc48a20e Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 17:22:07 +0100
Subject: [PATCH 07/13] Update runtime.yml

---
 tasks/runtime.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tasks/runtime.yml b/tasks/runtime.yml
index b4607482..3c9d4005 100644
--- a/tasks/runtime.yml
+++ b/tasks/runtime.yml
@@ -112,7 +112,7 @@
     mode: "0644"
   when:
     - openhpc_enable.control | default(false)
-    - openhpc_mpi_conf | length > 0
+    - (openhpc_mpi_default_config | combine(openhpc_mpi_config)) | length > 0
   notify:
     - Restart slurmctld service
   register: ohpc_mpi_conf

From 278f55a550bfd24aa82b502c7e5cff8b7cd90587 Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 17:23:54 +0100
Subject: [PATCH 08/13] Update main.yml

---
 defaults/main.yml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/defaults/main.yml b/defaults/main.yml
index 5ba72e16..96be7008 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -50,8 +50,10 @@ openhpc_config: {}
 openhpc_cgroup_config: {}
 openhpc_gres_template: gres.conf.j2
 openhpc_cgroup_template: cgroup.conf.j2
+
 openhpc_mpi_template: mpi.conf.j2
-openhpc_mpi_conf: []
+openhpc_mpi_default_config: {}
+openhpc_mpi_config: {}
 
 openhpc_state_save_location: /var/spool/slurm
 openhpc_slurmd_spool_dir: /var/spool/slurm

From 5c9fa0111b91774afbce4625941f003ce0858437 Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 17:24:32 +0100
Subject: [PATCH 09/13] Update mpi.conf.j2

---
 templates/mpi.conf.j2 | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/templates/mpi.conf.j2 b/templates/mpi.conf.j2
index d212c759..4e9b329b 100644
--- a/templates/mpi.conf.j2
+++ b/templates/mpi.conf.j2
@@ -1,4 +1,6 @@
 # {{ ansible_managed }}
-{% for line in openhpc_mpi_conf %}
-{{ line }}
+{% for k, v in openhpc_mpi_default_config | combine(openhpc_mpi_config) | items %}
+{%  if v != "omit" %}{# allow removing items using setting key: omit #}
+{{ k }}={{ v | join(',') if (v is sequence and v is not string) else v }}
+{%  endif %}
 {% endfor %}

From a53771101649be74eb7913b467e97fa79315964d Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Wed, 17 Sep 2025 17:30:11 +0100
Subject: [PATCH 10/13] Update README.md

---
 README.md | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/README.md b/README.md
index 18c5853f..f421e5e7 100644
--- a/README.md
+++ b/README.md
@@ -126,6 +126,13 @@ used to supplement or override the template defaults. Templated parameters can
 also be removed by setting the value to the literal string `'omit'` - note
 that this is *not the same* as the Ansible `omit` [special variable](https://docs.ansible.com/ansible/latest/reference_appendices/special_variables.html#term-omit).
 
+`openhpc_mpi_config`: Optional. Mapping of additional parameters and values for
+[mpi.conf](https://slurm.schedmd.com/mpi.conf.html). Keys are mpi.conf
+parameter names and values are lists or strings as appropriate. This can be
+used to supplement or override the template defaults. Templated parameters can
+also be removed by setting the value to the literal string `'omit'` - note
+that this is *not the same* as the Ansible `omit` [special variable](https://docs.ansible.com/ansible/latest/reference_appendices/special_variables.html#term-omit).
+
 `openhpc_ram_multiplier`: Optional, default `0.95`. Multiplier used in the calculation: `total_memory * openhpc_ram_multiplier` when setting `RealMemory` for the partition in slurm.conf. Can be overriden on a per partition basis using `openhpc_slurm_partitions.ram_multiplier`. Has no effect if `openhpc_slurm_partitions.ram_mb` is set.
 
 `openhpc_state_save_location`: Optional. Absolute path for Slurm controller state (`slurm.conf` parameter [StateSaveLocation](https://slurm.schedmd.com/slurm.conf.html#OPT_StateSaveLocation))

From cfe864f7c09e7bf08398909d7ad0e96c32297144 Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Fri, 3 Oct 2025 15:56:33 +0100
Subject: [PATCH 11/13] Update main.yml

---
 defaults/main.yml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/defaults/main.yml b/defaults/main.yml
index 96be7008..29e33adf 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -52,7 +52,6 @@ openhpc_gres_template: gres.conf.j2
 openhpc_cgroup_template: cgroup.conf.j2
 
 openhpc_mpi_template: mpi.conf.j2
-openhpc_mpi_default_config: {}
 openhpc_mpi_config: {}
 
 openhpc_state_save_location: /var/spool/slurm

From f9ebaf59714445f9e269182f563af6a24c858863 Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Fri, 3 Oct 2025 15:58:31 +0100
Subject: [PATCH 12/13] Update mpi.conf.j2

---
 templates/mpi.conf.j2 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/templates/mpi.conf.j2 b/templates/mpi.conf.j2
index 4e9b329b..986b62cf 100644
--- a/templates/mpi.conf.j2
+++ b/templates/mpi.conf.j2
@@ -1,5 +1,5 @@
 # {{ ansible_managed }}
-{% for k, v in openhpc_mpi_default_config | combine(openhpc_mpi_config) | items %}
+{% for k, v in openhpc_mpi_config.items %}
 {%  if v != "omit" %}{# allow removing items using setting key: omit #}
 {{ k }}={{ v | join(',') if (v is sequence and v is not string) else v }}
 {%  endif %}

From 3b502087214dd33b5de6a88b652fa36afc87f58a Mon Sep 17 00:00:00 2001
From: bertiethorpe <84867280+bertiethorpe@users.noreply.github.com>
Date: Fri, 3 Oct 2025 16:04:41 +0100
Subject: [PATCH 13/13] Update runtime.yml

---
 tasks/runtime.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tasks/runtime.yml b/tasks/runtime.yml
index 3c9d4005..c2e30d45 100644
--- a/tasks/runtime.yml
+++ b/tasks/runtime.yml
@@ -112,7 +112,7 @@
     mode: "0644"
   when:
     - openhpc_enable.control | default(false)
-    - (openhpc_mpi_default_config | combine(openhpc_mpi_config)) | length > 0
+    - openhpc_mpi_config | length > 0
   notify:
     - Restart slurmctld service
   register: ohpc_mpi_conf