MariaDB Galera high CPU without any actual load

[Yaron ben shalom]

We have a 3 node MariaDB Galera cluster running on Ubuntu 16.04 virtual machines (VMware).

This runs perfectly well in our development environment but in UAT and Production (at the Client's site), the nodes experience high CPU (around 37% in UAT) without any actual load from the system using the cluster.

MariaDB version: 10.1.22

Galera provider version: 25.3.19(r3667)

PS shows 4 threads running  /usr/sbin/mysqld --wsrep_start_position=<GUID>:<NUMBER> for a very long time on all nodes in all environments.

The GUID is the same for all nodes, the NUMBER is not - but this happens in development as well and the high CPU issue does not occur there.

We activated PERFORMANCE_SCHEMA, but fail to find any useful information there.

All nodes are Synced and Ready.

Any information would be more than welcome.

[Yaron ben shalom]

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