Anyone can tell me what is "WAFL Write cleaning" displayed under node - system utilization ?
Is that activity trriggered for free-space-realloc?
Last night at ~23:00 I do se increased write latency for up to 200ms with no increase of write workload and some increase of read requests. Disk are busy but less loaded than few hours before. The only corelation is with "WAFL Write cleaning".
What can I do to mitigate this latency in the future or what to check further ?