alter database suspend

Hi!
Can anyone tell me at which point the i/o activity gets suspended? For instance if a suspend happens

• when only one out of three or four controlfiles has been written
• ditto for redo mirrored redo logs
• ARCn is in the middle of archiving a nice big 512MB redo log, will those writes be completed?

Lots of Greetings!
Volker

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