I have a trace file created by my archiver process. Does anyone know what this means:

Redo thread mounted by this instance: 0
Oracle process number: 8
Unix process pid: 228340, image: oracle@casprd01 (ARC0)

*** SESSION ID:(7.1) 2001-12-27 15:21:05.013
*** 2001-12-27 15:21:05.013