This figure illustrates how online redo log files are archived over time. In this case there is only one archive process (ARC0) and only one archived redo log. It shows the following sequence:

1. LGWR writes to online redo log file 1 (Log0001).
2. When Log0001 is full, LGWR begins writing to redo log file 2 (Log0002), and ARC0 writes Log0001 to the archived redo log 0001.
3. When Log0002 is full, LGWR begins writing to redo log file 3 (Log0003), and ARC0 writes Log0002 to the archived redo log 0002.
4. When Log0003 is full, LGWR begins writing to redo log file 4 (Log0004), and ARC0 writes Log0003 to the archived redo log 0003.
5. and so on.