TPAM v2.4 uses the SQL (MSDE) which is limited to a maximum of 8 concurrent SQL connections. TPAM Enterprise class appliances use SQL (Full) and has no limit on the number of concurrent connections.
1. Migrate to the latest TPAM 2.5 (recommended)
2. Upgrade from TPAM 2.4 standard appliances to TPAM 2.4 enterprise class appliances
3. Limit the number of background processes in their existing environment which run during peak times. For example, reduce any data extracts, reduce the automation threads, increase the automation engine retry frequency intervals, avoid running large reports such as the user entitlement report, remove any used systems/accounts, change the daily maintenance job to run at an off peak time which does not conflict with the backup. Reduce retention periods in Global Settings.