We recently upgraded from 12c (12.1) to 18c, we are using enterprise edition. Instead of installing in a new oracle home on one of the fast disk, IT opted to install binaries on a new disk that is much slower than the data disks. All data files, redo logs, trace and dump files go to disks that are 2500 iops. The oracle binaries are on a disk that is 120 iops. We are in AWS using Oracle Linux 6.6 with latest security patches. Since this upgrade we have been having problems with the system, mainly Flash Back Data Archive (FBDA). Roughly every 24.5 hours we get an issue reported in OEM that there is contention and user I/O waits concerning the FBDA process, yet the disk that the FBDA tables are on are the same fast disk and we did not have this trouble in 12c. We opened a ticket with Oracle support and they have not found anything wrong and that in the upgrade FBDA code was not touched. In monitoring the iops on the new binary disk, in never gets above 80, but at the point in time of the FBDA contention, it is only about 2 iops. With everything else the same as 12c only the new binary disk is different, do the IOPS on the disk the Oracle Binaries are stored need to be the same as the data disks?