ceph-common: calculate vm.min_free_kbytes

based on the os memory we calculate the value for vm.min_free_kbytes

Signed-off-by: Sébastien Han <seb@redhat.com>

diff --git a/roles/ceph-common/defaults/main.yml b/roles/ceph-common/defaults/main.yml
index d8bb1f3806c87cdcf39ddbcbdea101067ffd46da..cfe014bcc3d59c837cd342a5d615f5bde4d27f54 100644 (file)
--- a/roles/ceph-common/defaults/main.yml
+++ b/roles/ceph-common/defaults/main.yml
@@ -295,7 +295,7 @@ os_tuning_params:
   - { name: fs.file-max, value: 26234859 }\r
   - { name: vm.zone_reclaim_mode, value: 0 }\r
   - { name: vm.vfs_cache_pressure, value: 50 }\r
-  - { name: vm.min_free_kbytes, value: 4194303 }\r
+  - { name: vm.min_free_kbytes, value: "{{ vm_min_free_kbytes }}" }\r
 \r
 \r
 ##########\r

diff --git a/roles/ceph-common/tasks/misc/system_tuning.yml b/roles/ceph-common/tasks/misc/system_tuning.yml
index 511d8a663ddec46665de61e696f4ef625896143f..874bd005941766924650817a3e10c6fe27c22d68 100644 (file)
--- a/roles/ceph-common/tasks/misc/system_tuning.yml
+++ b/roles/ceph-common/tasks/misc/system_tuning.yml
@@ -16,6 +16,10 @@
   failed_when: false
   when: disable_swap
 
+- name: calculate vm.min_free_kbytes
+  set_fact:
+    vm_min_free_kbytes: "{{ 4194303 if ansible_memtotal_mb >= 49152 else (ansible_memtotal_mb * 1024 / 100)|int }}"
+
 - name: apply operating system tuning
   sysctl:
     name: "{{ item.name }}"