
This change add a new lib/host-mem file and moves the existing ksm support to a new configure_ksm function. Additional support for ksmtuned is added with a new flag "ENABLE_KSMTUNED" which defaults to true. This change also adds support for zswap. zswap is disabled by default. When enabled on ubuntu lz4 will be used as the default compressor and z3fold as the zpool. On non debian distros the compressor and zpool are not set. The default values should result in very low overhead although the zstd compressor may provide better overall performance in ci or with slow io due to the higher compression ratio. Additionally memory and network sysctl tunings are optionally applied to defer writes, prefer swapping and optimise tcp connection startup and keepalive. The sysctl tunings are disabled by default The base devstack job has been modifed to enable zram and sysctl tuning. Both ksm and zswap are wrapped by a tune_host function which is now called very early in devstack to ensure they are configured before any memory/network intensive operations are executed. The ci jobs do not enable this functionality by default. To use this functionaltiy define ENABLE_SYSCTL_MEM_TUNING: true ENABLE_SYSCTL_NET_TUNING: true ENABLE_ZSWAP: true in the devstack_localrc section of the job vars. Change-Id: Ia5202d5a9903492a4c18b50ea8d12bd91cc9f135
DevStack is a set of scripts and utilities to quickly deploy an OpenStack cloud from git source trees.
Goals
- To quickly build dev OpenStack environments in a clean Ubuntu or RockyLinux environment
- To describe working configurations of OpenStack (which code branches work together? what do config files look like for those branches?)
- To make it easier for developers to dive into OpenStack so that they can productively contribute without having to understand every part of the system at once
- To make it easy to prototype cross-project features
- To provide an environment for the OpenStack CI testing on every commit to the projects
Read more at https://docs.openstack.org/devstack/latest
IMPORTANT: Be sure to carefully read stack.sh and any other scripts you execute before you run them, as they install software and will alter your networking configuration. We strongly recommend that you run stack.sh in a clean and disposable vm when you are first getting started.
Versions
The DevStack master branch generally points to trunk versions of OpenStack components. For older, stable versions, look for branches named stable/[release] in the DevStack repo. For example, you can do the following to create a Zed OpenStack cloud:
git checkout stable/zed
./stack.sh
You can also pick specific OpenStack project releases by setting the
appropriate *_BRANCH variables in the
localrc
section of local.conf (look in stackrc for the default set). Usually just
before a release there will be milestone-proposed branches that need to
be tested:
GLANCE_REPO=https://opendev.org/openstack/glance.git
GLANCE_BRANCH=milestone-proposed
Start A Dev Cloud
Installing in a dedicated disposable VM is safer than installing on your dev machine! Plus you can pick one of the supported Linux distros for your VM. To start a dev cloud run the following NOT AS ROOT (see DevStack Execution Environment below for more on user accounts):
./stack.sh
When the script finishes executing, you should be able to access OpenStack endpoints, like so:
- Horizon: http://myhost/
- Keystone: http://myhost/identity/v3/
We also provide an environment file that you can use to interact with your cloud via CLI:
# source openrc file to load your environment with OpenStack CLI creds
. openrc
# list instances
openstack server list
DevStack Execution Environment
DevStack runs rampant over the system it runs on, installing things and uninstalling other things. Running this on a system you care about is a recipe for disappointment, or worse. Alas, we're all in the virtualization business here, so run it in a VM. And take advantage of the snapshot capabilities of your hypervisor of choice to reduce testing cycle times. You might even save enough time to write one more feature before the next feature freeze...
stack.sh
needs to have root access for a lot of tasks,
but uses sudo
for all of those tasks. However, it needs to
be not-root for most of its work and for all of the OpenStack services.
stack.sh
specifically does not run if started as root.
DevStack will not automatically create the user, but provides a
helper script in tools/create-stack-user.sh
. Run that (as
root!) or just check it out to see what DevStack's expectations are for
the account it runs under. Many people simply use their usual login (the
default 'ubuntu' login on a UEC image for example).
Customizing
DevStack can be extensively configured via the configuration file local.conf. It is likely that you will need to provide and modify this file if you want anything other than the most basic setup. Start by reading the configuration guide for details of the configuration file and the many available options.