From 023334dfcb02d0303b778be8a7b62e80e9333354 Mon Sep 17 00:00:00 2001
From: "binhong.hua" <huabinhong@unitedstack.com>
Date: Thu, 17 Jan 2019 15:13:42 +0800
Subject: [PATCH] optimize qemu.conf

bump up the max_files to 32768 and max_processes to 131072.
when nova used ceph as backend, the default limit 1024 is not enough.
each connection from rbd image to osd needs 1 fd and 2 threads. if we
have 200 osds, we need 200 fds and 400 threads for 1 image.

Change-Id: I94c3ec111473ea2ccacdea5dbbf3fdc9c569859f
---
 ansible/roles/nova/defaults/main.yml                      | 7 +++++++
 ansible/roles/nova/templates/qemu.conf.j2                 | 3 +++
 releasenotes/notes/add_qume_options-8e9f040d0bc36fe6.yaml | 7 +++++++
 3 files changed, 17 insertions(+)
 create mode 100644 releasenotes/notes/add_qume_options-8e9f040d0bc36fe6.yaml

diff --git a/ansible/roles/nova/defaults/main.yml b/ansible/roles/nova/defaults/main.yml
index b6c0c1aeff..10d6f64c9b 100644
--- a/ansible/roles/nova/defaults/main.yml
+++ b/ansible/roles/nova/defaults/main.yml
@@ -397,6 +397,13 @@ nova_enabled_notification_topics: "{{ nova_notification_topics | selectattr('ena
 vmware_vcenter_datastore_regex: ".*"
 ovs_bridge: "nsx-managed"
 
+####################
+# Libvirt/qemu
+####################
+# The number of max files qemu can open
+qemu_max_files: 32768
+# The number of max processes qemu can open
+qemu_max_processes: 131072
 
 ####################
 # Kolla
diff --git a/ansible/roles/nova/templates/qemu.conf.j2 b/ansible/roles/nova/templates/qemu.conf.j2
index b926b7bb3f..82ecd7f233 100644
--- a/ansible/roles/nova/templates/qemu.conf.j2
+++ b/ansible/roles/nova/templates/qemu.conf.j2
@@ -2,3 +2,6 @@ stdio_handler = "file"
 
 user = "nova"
 group = "nova"
+
+max_files =  {{ qemu_max_files }}
+max_processes =  {{ qemu_max_processes }}
diff --git a/releasenotes/notes/add_qume_options-8e9f040d0bc36fe6.yaml b/releasenotes/notes/add_qume_options-8e9f040d0bc36fe6.yaml
new file mode 100644
index 0000000000..793796eb23
--- /dev/null
+++ b/releasenotes/notes/add_qume_options-8e9f040d0bc36fe6.yaml
@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    Bump up the max_files to 32768 and max_processes to 131072.
+    when nova used ceph as backend, the default limit 1024 is not enough.
+    each connection from rbd image to osd needs 1 fd and 2 threads. if we
+    have 200 osds, we need 200 fds and 400 threads for 1 image.