Release Notes

Release Notes

Couchbase Server 5.5.0 (Developer Build) is a significant update of the Couchbase Data Platform. This release specifically highlights agility, performance, and manageability and includes enhancements to existing services as well as new server and SDK components. Take a look at What's New? for a list of new features and improvements that are available in this release.

Couchbase Server 5.5.0 Developer Build was released in March 2018.


This pre-release version of Couchbase Server 5.5 (Developer Build) is intended for development purposes only. Some features are still in development and may have some rough edges and bugs, and may change significantly before the final GA release. This pre-release version is not supported in production.

The pre-release versions do not support upgrading from an earlier version of Couchbase Server.

Known Issues

Issue Description
MB-28453 Summary: Eventing service uses a feature in Memcached which is known to have a race condition that may cause Memcached to restart.

Summary: It is possible for a rebalance of the Analytics nodes to always fail if:

  • a bucket is in the disconnected state, and
  • the Analytics nodes are at different DCP states.
In that case a common DCP state (required for rebalancing) cannot be achieved as no new DCP mutations will be received by the Analytics nodes.
MB-26478 Summary: On Windows, a system limitation with the Analytics statistics may cause “system load” to have a negative value. Additionally, on Windows and mac OS, the statistics for “bytes read/sec” and “bytes written/sec” are not reported and always show zero.
MB-26065 Summary: Rebalance exits with reason "janitor_agent_servant_died". This was observed when the client connection was re-established, causing the RBAC privileges to be reloaded.
MB-23074 Summary: Performance issues may be observed when running Couchbase Server on CentOS 7.3 with kernel 3.10.0-514.6.
MB-17571 Summary: On an undersized node, the default memory quota assigned to all the selected services by the server might result in a failure.

Workaround: Adjust the memory allocations appropriately to work around this issue.

Fixed Issues

Web Console

Issue Description
MB-26418 With failed EXPLAIN queries, the error was not being checked before trying to render non-existent the query plan, causing a UI hang.