Skip to content
Percona Software for MongoDB Documentation

Rate this page
☆ ☆ ☆ ☆ ☆
Thanks for your feedback
Thank you! The feedback has been submitted.

For help, click the link below to get free database assistance or contact our experts for personalized support.

Get help from Percona

Percona ClusterSync for MongoDB 0.9.0 (2026-06-03)

We’re excited to announce Percona ClusterSync for MongoDB (PCSM) 0.9.0. This release introduces cross-version replication support, allowing replication from MongoDB 6.0 and 7.0 source clusters to MongoDB 8.0 targets. This capability helps simplify staged upgrades and migration workflows while maintaining continuous replication between supported MongoDB versions.

We also ship a Software Bill of Materials (SBOM) with every release, providing visibility into the components and dependencies included in each release.

Get started with PCSM

Release highlights

Cross-version support

PCSM now supports cross-version replication from MongoDB 6.0 and MongoDB 7.0 source clusters to MongoDB 8.0 target clusters. This enables staged upgrade and migration workflows while maintaining continuous replication between supported MongoDB versions.

At startup, PCSM validates the source and target MongoDB versions against the supported compatibility matrix. If the source cluster is running a higher major version than the target cluster, PCSM prevents replication from starting and exits with an error.

For more information, see the documentation.

Enhanced replication performance for large collections

Replication performance for large collections has been significantly improved, with benchmark tests showing up to 37.3% faster synchronization (approximately 1.4× faster).

Software Bill of Materials (SBOM)

Percona ClusterSync for MongoDB (PCSM) now provides Software Bills of Materials (SBOMs) for every release. SBOMs improve software supply chain transparency by documenting the components and dependencies included in a build. They are generated automatically as part of the release pipeline in the industry standard CycloneDX 1.6 format.

SBOMs are distributed through the following channels:

  • GitHub: The latest SBOM is placed in the root of the percona/percona-clustersync-mongodb main branch.

  • Binaries/Tarballs: An SBOM file is included in the root directory of the release archive.

  • Packages: For .deb and .rpm packages, the SBOM file is installed in a standard documentation directory such as /usr/share/doc/percona-clustersync-mongodb/.

  • Docker: The SBOM is attached directly to the Docker image as metadata.

Changelog

New features

  • PCSM-282: Added Software Bills of Materials (SBOMs) for PCSM releases. SBOMs are generated in the CycloneDX 1.6 format and distributed with release artifacts.

  • PCSM-286: Added support for cross-version replication from MongoDB 7.0 to MongoDB 8.0.

  • PCSM-289: Added support for cross-version replication from MongoDB 6.0 to MongoDB 8.0.

Improvements

  • PCSM-176: Introduced a finalization section to the /status endpoint to report failed, incomplete, or inconsistent indexes, eliminating the need to parse logs. This update also fixes inconsistent index detection in sharded clusters, ensuring accurate reporting across all data shards.

Bugs

  • PCSM-314: Fixed an issue where PCSM could crash during replication when processing an event against an item that did not exist in the target array, causing the replication to halt unexpectedly.

  • PCSM-323: Fixed an auto-segmentation issue where byte sizes were incorrectly passed as document counts, restoring parallelized read operations for large collection clones. This update also introduces a --clone-segment-size flag for explicit configuration and adds detailed logging for segmentation metrics.

Last update: June 3, 2026
Created: June 3, 2026