Ussuri Series Release Notes¶
Python 2.7 support has been dropped. The minimum version of Python now supported by placement is Python 3.6.
When a single resource provider receives many concurrent allocation writes, retries may be performed server side when there is a resource provider generation conflict. When those retries are all consumed, the client receives an HTTP 409 response and may choose to try the request again.
In an environment where high levels of concurrent allocation writes are common, such as a busy clustered hypervisor, the default retry count may be too low. See story 2006467
A new configuation setting,
[placement]/allocation_conflict_retry_count, has been added to address this situation. It defines the number of times to retry, server-side, writing allocations when there is a resource provider generation conflict.