kolla-ansible/doc/source/reference/resource-constraints.rst
Lakshmi Prasanna Goutham Pratapa 76210a2d85 Apply Resource Constraints to Openstack Services
This commit is to apply resource-constraints only to few OpenStack services.
Commit to apply constraints to other services will be made in coming commits.

Partially-Implements: blueprint resource-constraints

Change-Id: Icafa54baca24d2de64238222a5677b9d8b90e2aa
2018-07-25 17:05:04 +01:00

115 lines
2.5 KiB
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.. _resource-constraints:
=====================================
Resource Constraints in Kolla Ansible
=====================================
Overview
~~~~~~~~
Since the Rocky release it is possible to restrict
the resource usage of deployed containers. In Kolla Ansible,
container resources to be constrained are referred to as dimensions.
The `Docker documentation <https://docs.docker.com/config/containers/resource_constraints/>`__
provides information on container resource constraints.
The resources currently supported by Kolla Ansible are:
.. code-block:: console
cpu_period
cpu_quota
cpu_shares
cpuset_cpus
cpuset_mems
mem_limit
mem_reservation
memswap_limit
kernel_memory
blkio_weight
.. end
Pre-deployment Configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dimensions are defined as a mapping from a Docker resource name
.. list-table:: Resource Constraints
:widths: 25 25 25
:header-rows: 1
* - Resource
- Data Type
- Default Value
* - cpu_period
- Integer
- 0
* - blkio_weight
- Integer
- 0
* - cpu_quota
- Integer
- 0
* - cpu_shares
- Integer
- 0
* - mem_limit
- Integer
- 0
* - memswap_limit
- Integer
- 0
* - mem_reservation
- Integer
- 0
* - cpuset_cpus
- String
- ''(Empty String)
* - cpuset_mems
- String
- ''(Empty String)
The variable ``default_container_dimensions`` sets the default dimensions
for all supported containers, and by default these are unconstrained.
Each supported container has an associated variable,
``<container name>_dimensions``, that can be used to set the resources
for the container. For example, dimensions for the ``nova_libvirt``
container are set via the variable ``nova_libvirt_dimensions``.
For example,
to constrain the number of CPUs that may be used by all supported containers,
add the following to the dimensions options section in
``/etc/kolla/globals.yml``:
.. code-block:: yaml
default_container_dimensions:
cpuset_cpus: "1"
.. end
For example, to constrain the number of CPUs that may be used by
the ``nova_libvirt`` container, add the following to the dimensions
options section in ``/etc/kolla/globals.yml``:
.. code-block:: yaml
nova_libvirt_dimensions:
cpuset_cpus: "2"
.. end
Deployment
~~~~~~~~~~
To deploy resource constrained containers, run the deployment as usual:
.. code-block:: console
$ kolla-ansible deploy -i /path/to/inventory
.. end