DR Failover data loss

Hi,

We have a 2 node RAC database with a physical standby at a remote location in MAXIMUM PERFORMANCE mode. This ensures that the primary database works smoothly in case there are any issues with the DR site. Opting this also means that there might be data loss in case of the primary site going down. The data loss will be for all the archive logs that are not transported and applied at the standby database. That might be a few minutes in case of peak time and a few hours in case there is no load. Is there some way to find out how much will be the data loss time? 10 minutes / 20 minutes? Also is there some way to ensure that archive logs gets generated every N minutes whether the log file is full or not? I've looked at FAST_MTTR_TARGET but it does not help. It is set to 300 but there are occurances wherein the log file has not been generated for 4-5 hours in our case.

Thanks,

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