Examining Redo Log File Switches

Sometimes the DBA needs to get an idea of when and how often redo log switches occur. There are two main reasons for this. First, the online redo log member files might be too small and thus too many log switches are occurring. And second, there may be periods of peak database activity that stress or overwhelm the current online redo log files. In either case, the DBA is essentially looking for a very simple historical display of online redo log switching activity. TOAD offers the Log Switch Frequency Map screen shown in Figure 6.62 and located on the main menu at DBA Log Switch Frequency Map. It shows both by day and hour all the online redo log switching activity for the database.

Figure 6.62. TOAD Log Switch Frequency Map screen.