Assuming regular basis workload of the database generates 1GB of data in redologs files every hour. What number and size of the redologs files might be appropriate for a good performance?
It's much more interesting how much redo data will be generated during the peak hours! So plan for the peaks, not for the regular workload!
Some DBAs say: size your online redo logs, so that it won't be switched more than 3-6 times per hour during peak times.
And it's better to make it bit bigger (add some buffer for future harder peaks), but make sure that you back them up more often, so that you won't loose too much changes when you will have to do restore and recovery.
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