The maintenance manager schedules and runs background tasks. At any given point in time, the maintenance manager is prioritizing the next task based on improvements needed at that moment, such as relieving memory pressure, improving read performance, or freeing up disk space.
The number of worker threads dedicated to running background tasks can be
controlled by setting
With Kudu 1.4, the maintenance manager features improved utilization of
the configured maintenance threads. Previously, maintenance work would only be scheduled a
maximum of 4 times per second, but now maintenance work will be scheduled immediately whenever
any configured thread is available. Make sure that the
--maintenance_manager_num_threads property is set to at most a 1:3 ratio for
Maintenance Manager threads to the number of data directories (for spinning disks). This will
improve the throughput of write-heavy workloads.