You must have a Monitoring console as it becomes handy and also to get the complete information about you enviornment.
You can monitor a lot of aspect of your enviornment. The dashoboard will give you the complete insight of your indexing performances.
The dash board will give you plenty of information about your indexes and volumes such as:
Disk usage by index
Index and volume size over time
Statistics for bucket types
And viewing this dashboard will give you all the requred information. I would suggest you to read the below document.