The requirements for Vacuum will depend on your application needs and the rate of arrival of new data. Vacuuming removes old versions of data.
If you need to be able to query earlier versions of data many months after the original ingest time, then it is likely that you will not vacuum older data often.
For applications that always operate on the latest version of data, then the main concern is to not break currently running queries. It will also depend on how much data is ingested daily.
For many applications , vacuuming weekly or nightly will be sufficient.
