From a039f8397702d15718ebcec0fdb9cfeb6155f6a1 Mon Sep 17 00:00:00 2001 From: Matt Riedemann Date: Tue, 4 Sep 2018 12:11:57 -0400 Subject: [PATCH] Document unset/reset wrinkle for *_allocation_ratio options This is a follow up to I43a23a3290db0c835fed01b8d6a38962dc61adce which makes the cpu/disk/ram_allocation_ratio config "sticky" in that once set to a non-default value, it is not possible to reset back to the default behavior (when config is 0.0) on an existing compute node record by unsetting the option from nova.conf. To reset back to the defaults, the non-0.0 default would have to be explicitly put into config, so cpu_allocation_ratio=16.0 for example. Alternatively operators could delete the nova-compute service record via the DELETE /os-services/{service_id} REST API and restart the nova-compute service to get a new compute_nodes record, but that workaround is messy and left undocumented in config. Change-Id: I908615d82ead0f70f8e6d2d78d5dcaed8431084d Related-Bug: #1789654 (cherry picked from commit c45adaca5dd241408f1e29b657fe6ed42c908b8b) --- nova/conf/compute.py | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/nova/conf/compute.py b/nova/conf/compute.py index 436da12ec9ea..016d77802ad9 100644 --- a/nova/conf/compute.py +++ b/nova/conf/compute.py @@ -401,7 +401,9 @@ configuration value if no per-aggregate setting is found. NOTE: This can be set per-compute, or if set to 0.0, the value set on the scheduler node(s) or compute node(s) will be used -and defaulted to 16.0. +and defaulted to 16.0. Once set to a non-default value, it is not possible +to "unset" the config to get back to the default behavior. If you want +to reset back to the default, explicitly specify 16.0. NOTE: As of the 16.0.0 Pike release, this configuration option is ignored for the ironic.IronicDriver compute driver and is hardcoded to 1.0. @@ -428,7 +430,9 @@ configuration value if no per-aggregate setting found. NOTE: This can be set per-compute, or if set to 0.0, the value set on the scheduler node(s) or compute node(s) will be used and -defaulted to 1.5. +defaulted to 1.5. Once set to a non-default value, it is not possible +to "unset" the config to get back to the default behavior. If you want +to reset back to the default, explicitly specify 1.5. NOTE: As of the 16.0.0 Pike release, this configuration option is ignored for the ironic.IronicDriver compute driver and is hardcoded to 1.0. @@ -459,7 +463,9 @@ instances. NOTE: This can be set per-compute, or if set to 0.0, the value set on the scheduler node(s) or compute node(s) will be used and -defaulted to 1.0. +defaulted to 1.0. Once set to a non-default value, it is not possible +to "unset" the config to get back to the default behavior. If you want +to reset back to the default, explicitly specify 1.0. NOTE: As of the 16.0.0 Pike release, this configuration option is ignored for the ironic.IronicDriver compute driver and is hardcoded to 1.0.