Pike Series Release Notes¶

16.0.0¶

Capping the default value for the variables heat_api_workers and heat_engine_workers to 16 when the user doesn’t configure these variables. Default value is half the number of vCPUs available on the machine with a capping value of 16.

New variables have been added to allow a deployer to customize a heat systemd unit file to their liking.

The task dropping the heat systemd unit files now uses the config_template action plugin allowing deployers access to customize the unit files as they see fit without having to load extra options into the defaults and polute the generic systemd unit file with jinja2 variables and conditionals.

For the os_heat role, the systemd unit TimeoutSec value which controls the time between sending a SIGTERM signal and a SIGKILL signal when stopping or restarting the service has been reduced from 300 seconds to 120 seconds. This provides 2 minutes for long-lived sessions to drain while preventing new ones from starting before a restart or a stop. The RestartSec value which controls the time between the service stop and start when restarting has been reduced from 150 seconds to 2 seconds to make the restart happen faster. These values can be adjusted by using the heat_*_init_config_overrides variables which use the config_template task to change template defaults.

The heat-api, heat-api-cfn, and heat-api-cloudwatch services have moved to run as a uWSGI applications. You can set the max number of WSGI processes, the number of processes, threads, and buffer size utilizing the heat_wsgi_processes_max, heat_wsgi_processes, heat_wsgi_threads, and heat_wsgi_buffer_size. Additionally, you can override any settings in the uWSGI ini configuration file using the heat_api_uwsgi_ini_overrides, heat_api_cfn_uwsgi_ini_overrides, and heat_api_cloudwatch_uwsgi_ini_overrides settings. The uWSGI applications will listen on the addresses specified by heat_api_uwsgi_bind_address, heat_api_cfn_uwsgi_bind_address, and heat_api_cloudwatch_uwsgi_bind_address respectively. Which all default to 0.0.0.0.

For the os_heat role, the systemd unit TimeoutSec value which controls the time between sending a SIGTERM signal and a SIGKILL signal when stopping or restarting the service has been reduced from 300 seconds to 120 seconds. This provides 2 minutes for long-lived sessions to drain while preventing new ones from starting before a restart or a stop. The RestartSec value which controls the time between the service stop and start when restarting has been reduced from 150 seconds to 2 seconds to make the restart happen faster. These values can be adjusted by using the heat_*_init_config_overrides variables which use the config_template task to change template defaults.

Remove heat_rpc_backend option due to deprecation of rpc_backend option in oslo.messaging.