Hello everyone, thanks for a very productive PTG for the Hibiscus cycle. Below is a brief summary of the highlights. The summary and transcribed etherpad[^1] notes are captured on our wiki[^2]. # Cinder 2026.2 Hibiscus PTG Summary **Date:** April 20–24, 2026 (Virtual) --- ## 2026.1 Gazpacho Retrospective - Every release deadline was missed by a few days (including client libraries and os-brick). - Agreement to be stricter about release deadlines and send explicit deadline reminders. - No concrete solution yet for prioritizing reviews to ease deadline pressure. --- ## 2026.2 Release Planning - Discussion of adding Cinder-specific entries to the Hibiscus release schedule. - Contributor documentation needs updating: deliverables list, meeting cadence (resume monthly video meeting), and explicit os-brick readiness dates. - Add a "new driver declaration deadline" early in the cycle to allow time for review planning. - **Action:** agalica to review contributor docs for clarity and correctness. - **Action:** jbernard to consider moving the review festival to a single block after the weekly meeting. --- ## Scheduler Sending Jobs to Disabled Hosts (zigo) - Patch under review: [!979641](https://review.opendev.org/c/openstack/cinder/+/979641). - Reviewers need a bug filed with more detail to understand the fix; a possible race condition is suspected. - Patch needs unit tests. The question of whether "frozen" hosts are also affected needs investigation. --- ## Supply WWID Instead of LUN Numbers (rajat) - Current iSCSI/FC logic uses LUN numbers, which can change or overlap under certain conditions. - Proposal: use WWID (which is stable for the lifetime of a LUN) instead, with LUN-based code kept as a fallback. - Drivers will need updates; strategy is to start with the LVM driver (LIO target) for iSCSI. - A tempest test should be added to enforce the new contract, with a grace period of a couple of cycles for vendor CIs. - **Action:** rajat to send a message to the mailing list for vendor feedback. --- ## New Driver Status (erlon) Three new drivers are currently in review for Hibiscus: - ZTE: [!969207](https://review.opendev.org/c/openstack/cinder/+/969207) - LINSTOR: [!964289](https://review.opendev.org/c/openstack/cinder/+/964289) - HPE Alletra MP: [!969373](https://review.opendev.org/c/openstack/cinder/+/969373) Goal is to compile a driver list early in the cycle to direct review resources appropriately. --- ## RBD Encryption Performance (rsasitilak) - Proposal to use the librbd engine to bypass the QEMU single-thread bottleneck during encrypted volume I/O. - Skepticism about the performance improvement claims and the level of rework required to the current RBD implementation. - **Action:** jbernard to respond to the [mailing list thread](https://lists.openstack.org/archives/list/openstack-discuss@lists.openstack....) requesting more detailed benchmarking information. --- ## Volume Migration with Snapshots (fqi) - Currently, migrating a volume that has snapshots fails. - Proposal to query drivers for available functionality and use it when present, broken into three stages. - Blueprint: [volume-migration-with-snapshot](https://blueprints.launchpad.net/cinder/+spec/volume-migration-with-snapshot) - Open questions remain around snapshot semantics (snapshots becoming separate volumes) and vendor-specific COW implementations. --- ## HPE Alletra MP Driver (Jyotsna/raghavendrat) - New driver in review: [!969373](https://review.opendev.org/c/openstack/cinder/+/969373). - Uses the `hpe-storage-flowkit-py` library as an intermediary layer to separate backend-specific logic from driver code. --- ## Backup Container Name Templates (noonedeadpunk) - Spec: [!962306](https://review.opendev.org/c/openstack/cinder-specs/+/962306); patch: [!962909](https://review.opendev.org/c/openstack/cinder/+/962909). - Key concern: when the template changes in config, operators must manually migrate existing backup data. - Discussion of adding a DB field to track the actual (post-template) container name separately from the configured value. --- ## CBT-Based Incremental Backup (hong-p) - Spec: [!985089](https://review.opendev.org/c/openstack/cinder-specs/+/985089). - Proposal to optimize incremental backups using Changed Block Tracking (CBT). - Nova involvement required for attached volumes; Cinder implementation useful for bare-metal attachments. - No philosophical objections from the team; free to proceed. Open questions include where to store CBT data and the need for an external REST API. --- ## Logging Guidelines (Anoop_Shukla / NetApp) - Proposal for a dedicated logging best-practices document for Cinder driver authors, covering log level definitions and usage of the `@volume_utils.trace` decorator. - Working document: [OpenStack Cinder Logging Guidelines etherpad](https://etherpad.opendev.org/p/OpenStack_Cinder_Logging_Guidelines). - Seeking community feedback. --- ## RBD Performance: Direct Import (ricolin) - Using QEMU to output directly rather than `rbd import` yields at least a 20% I/O performance improvement for large (>1 TB) volumes, including encrypted volumes. - Relevant patches: - Non-encrypted: [!972263](https://review.opendev.org/c/openstack/cinder/+/972263) - Encrypted (direct import): [!933006](https://review.opendev.org/c/openstack/cinder/+/933006) - Encrypted (direct volume creation): [!910700](https://review.opendev.org/c/openstack/cinder/+/910700) - Alternative encrypted approach (rajat): [!955273](https://review.opendev.org/c/openstack/cinder/+/955273) --- ## Replication v3 (rajat) - Spec: [!985952](https://review.opendev.org/c/openstack/cinder-specs/+/985952). - Extends replication to support finer-grained failover (per-volume, per-pool, per-backend). - Includes automation of failover for synchronous replication and cross-cluster failover with security guards. - Safeguards needed to prevent overlap between replication granularities. --- ## 3rd-Party CI Systems (simondodsley) - Current tooling (SoftwareFactory moving to OpenShift) is not sustainable for all vendors. - Proposal to create a standard, simple CI template for running Cinder and os-brick tests, reporting to Gerrit, and storing logs in a GitHub repository with a standard URL format. --- ## NetApp Topics (jayanan) - Per-pool image cache enhancements. - Replication over Fibre Channel. - Best practices for raising dependent patches (noted: `git-restack` tool). - ONTAP REST vs. ZAPI migration gaps. --- ## Friday Patch Review - General patch review session. - Kubernetes lock support patch flagged for attention: [!956528](https://review.opendev.org/c/openstack/cinder/+/956528). [^1]: https://etherpad.opendev.org/p/cinder-hibiscus-ptg [^2]: https://wiki.openstack.org/wiki/CinderHibiscusPTGSummary