Cache and stores. New API endpoints expose cache clean and prune operations, giving operators an HTTP-driven path to manage cached image data rather than relying solely on out-of-band tooling. On the storage side, the S3 store no longer embeds credentials in the location URI it persists — a net removal of several hundred lines as credential handling is pulled out of the stored location and resolved separately.

Performance and policy. The image import worker pool has been switched from futurist to the stdlib concurrent.futures, trimming a dependency in a hot path. Policy scope enforcement checks and their tests were also tightened up.

Stability and tooling. glance-manage now honors --config-dir, closing a long-standing gap for deployments that split config across directories. Smaller fixes cover a Python shebang, a stray space in an exception message, qemu-utils in the unit-test job, and a rally image-location update.

Import task hardening. Beyond the threading fix, import URI filtering is now applied to legacy import tasks (landed twice, including a backport), closing a gap where the legacy path bypassed the URI allow/deny checks used by the newer flows. Quota accounting also gets tighter: upfront quota checks now use the known image size when available rather than deferring to post-upload reconciliation.

API reference and samples. The download API reference picks up missing documentation, store-info response samples are corrected, and smaller doc patches note that hw_rng_model has had no effect since Ussuri and mention Hyper-V Enlightenments under os_type.

Housekeeping. The glance-grenade-centralized-cache Zuul job is removed, devstack moves to systemctl for service management, and an unused direct Pygments dependency is dropped.