openstack/charm-nova-cloud-controller
Code Issues Proposed changes

Adjust default of `ram-allocation-ratio` configuration option

Browse Source 
In modern hyper-converged architectures the upstream default of
1.5 does not really fit.

Set to 0.98 to give some headroom on the compute nodes and add
a note about the potential need to adjust this value further.

Change-Id: I64e3379686128dd7f222bdfae133a6c90e8f3ef0
Closes-Bug: #1818234
This commit is contained in:
Frode Nordahl
2019-03-01 22:53:26 +01:00
parent c6c0e46c68
commit fe0ba3b883
2 changed files with 6 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
config.yaml
View File

@@ -217,12 +217,16 @@ options:
at the expense of instance performance. at the expense of instance performance.
ram-allocation-ratio: ram-allocation-ratio:
type: float type: float
default: 1.5 default: 0.98
description: | description: |
The physical ram -> virtual ram ratio to use in the Nova scheduler. The physical ram -> virtual ram ratio to use in the Nova scheduler.
. .
Increasing this value will increase instance density on compute nodes Increasing this value will increase instance density on compute nodes
at the potential expense of instance performance. at the potential expense of instance performance.
.
NOTE: When in a hyper-converged architecture, make sure to make enough
room for infrastructure services running on your compute hosts by
adjusting this value.
disk-allocation-ratio: disk-allocation-ratio:
type: float type: float
default: 1.0 default: 1.0

2
tests/basic_deployment.py
View File

@@ -834,7 +834,7 @@ class NovaCCBasicDeployment(OpenStackAmuletDeployment):
services['apache2'] = conf_file services['apache2'] = conf_file
# Expected default and alternate values # Expected default and alternate values
flags_default = 'cpu-allocation-ratio=16.0,ram-allocation-ratio=1.5' flags_default = 'cpu-allocation-ratio=16.0,ram-allocation-ratio=0.98'
flags_alt = 'cpu-allocation-ratio=32.0,ram-allocation-ratio=3.0' flags_alt = 'cpu-allocation-ratio=32.0,ram-allocation-ratio=3.0'
set_default = {'config-flags': flags_default} set_default = {'config-flags': flags_default}
set_alternate = {'config-flags': flags_alt} set_alternate = {'config-flags': flags_alt}