Technology Preview

This section provides an overview of Technology Preview features introduced or updated in this release of IBM Storage Ceph.

Important: Technology Preview features are not supported with IBM production service level agreements (SLAs), might not be functionally complete, and IBM does not recommend using them for production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

Ceph File System (CephFS)

Support for CephFS snapshot mirroring

With this feature you can replicate a CephFS to a remote CephFS on another Ceph storage cluster. Snapshot synchronization copies snapshot data to a remote Ceph File System, and creates a new snapshot on the remote target with the same name. You can configure specific directories for snapshot synchronization.

Note: To use CephFS snapshot mirroring, both the source and the target storage clusters must be running the same IBM Storage Ceph version.

For more information, see CephFS snapshot mirroring (Technology Preview).

Ceph Object Gateway

New per-user and per-bucket usage counters in Prometheus

Ceph Object Gateway now exports per-user and per-bucket usage counters via performance counters automatically collected by the ceph-exporter and made available in Prometheus. This provides low-overhead, real-time visibility into the following:

Per-bucket metrics: used bytes, utilized bytes, and number of objects
Per-user metrics: used bytes and number of objects
Cache performance metrics: cache hits, misses, updates, and evictions

Note: These metrics are disabled by default. To enable them, configure the appropriate settings in your Ceph Object Gateway configuration.

For more information, see Viewing Ceph Object Gateway per-user and per-bucket performance counters.

(BZ#2036531)

RADOS

Balanced primary placement groups can now be observed in a cluster

Previously, users could only balance primaries with the offline osdmaptool.

With this enhancement, autobalancing is available with the upmap balancer. Users can now choose between either the upmap-read or read mode. The upmap-read mode offers simultaneous upmap and read optimization. The read mode can only be used to optimize reads.

For more information, see Using the Ceph Manager balancer module.

(BZ#1870804)

Now supports tracking data availability score of a cluster

This release introduces a feature that tracks the data availability score of a Ceph cluster over time. The score represents how accessible your data is at any given moment, based on factors such as OSD health, placement group states, and redundancy policies.

By monitoring this metric, administrators gain a fact-based view of cluster reliability and can validate availability percentages (for example, 99.99%) against service-level objectives. This capability provides actionable insight into operational resilience and helps ensure confidence in Ceph as a storage platform for critical workloads.

For more information, see Track the data availability score of a cluster (Technology Preview).

(ISCE-2144)

Crimson-OSD

Crimson support

The Crimson project is an effort to build a replacement of ceph-osd daemon that is suited to the new reality of low latency, high throughput persistent memory, and NVMe technologies.

Crimson is the code name for crimson-osd, which is the next generation ceph-osd for multi-core scalability. It improves performance with fast network and storage devices, employing state-of-the-art technologies that includes DPDK and SPDK. BlueStore continues to support HDDs and SSDs. Crimson aims to be compatible with an earlier version of OSD daemon with the class ceph-osd.

Built on the Seastar C++ framework, Crimson is a new implementation of the core Ceph object storage daemon (OSD) component and replaces ceph-osd. The crimson-osd minimizes latency and increased CPU processor usage. It uses high-performance asynchronous IO and a new threading architecture that is designed to minimize context switches and inter-thread communication for an operation for cross communication.

For more information, see Crimson (Technology Preview).

(ISCE-1006)

NFS service

Added NFS over RDMA support for CephFS

Previously, NFS workloads over CephFS were limited to TCP-based communication, affecting performance in high-throughput environments.

With this feature, NFS over RDMA support is introduced, enabling high-performance, low-latency data access for NFS workloads.

(ISCE-2753)