Hi,
Sometimes, it helps if you can monitor the effective space usage through the day for sometime as this will be a better indicator of your space requirements.
As a rule, you should consider that no messages remain in the broker for more than a limited amount of time.
Unfortunately, long-running BPM processes hinder this.
If you find long standing messages maybe you should consider re-designing some of your flows/processes to save the messages on a more stable storage facility (like a database or files).
From my experience, Broker storage management is particularly hard and non-portable, with the added problems incurred during maintenance and migration/upgrades.
If you can architecture your systems to be able to ‘exhaust’ all the messages in the broker periodically, then you may be able to reclaim system storage by recreating the broker storage files (delete and create, no ‘quenching’ operation exists).
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