New Policy

Enable quotas. Select this to make Enterprise Vault archive according to the amount of space that is used on the target volume.

Start archiving at <percent> usage. Set this to be the maximum percentage of the space that you want to be occupied on the disk. Enterprise Vault begins archiving when the space allocation reaches this percentage and then continue until space usage reaches that specified in Stop archiving at <percent> usage.
Stop archiving at <percent> usage. Set this to be the percentage of the disk usage at which Enterprise Vault is to stop archiving. This sets an absolute limit on the amount of archiving that Enterprise Vault performs on the target volume.

If no more files meet the archiving criteria defined in the rules, Enterprise Vault stops archiving before this limit is reached.

You can adjust the settings to give you the optimum mix of performance and storage. By setting a fairly high value for Stop archiving at <percent> usage you ensure that the disk can maintain a high level of usage, while you can use start archiving at <percent> usage to ensure that the disk is never full.