How to Non-stop bucket flush

Couchbase server 6.0.0 is being used. The log is stored in the bucket of the couchbase and analysis data is generated using the bucket.
However, the size of the bucket storing the log is abnormally turned on, so I want to flush the bucket storing the log.
Is there a way to flush the bucket without interruption(Non-Stop)?
Our couchbase server is paired with 5 clusters and 5 xdcrs.
And what happens if flush on running bucket?
plz help me.