Way to much log switching!!!

9.2.0.4
Solaris 5.8

Is it unheard of to have redo logs sized at 500M, 750M or even 1G? Reading
the oracle documentation on redo log sizes it mentions that redo logs in the
gigabyte size is not abnormal. Does anyone have redo logs larger than 1G? If
so, have you had any issues with DBWR and checkpoint behavior? 

Currently, we have an ODS system with 3 redo log files sized at 200M each.
Looking at v$log_history, the logs are switching every 1 to 2 minutes. If a
200M log switches at 2 minutes then a 400M log should switch in 4 minutes
and 1G log should switch in 10 minutes. I've recommended to size the redo to
1G along with determining what is causing all the redo with Logminer. Is 20
minutes a good rule of thumb to go by when seeing how often the redo logs
switch?

The Oracle documentation reads:
        It is not possible to provide a specific size recommendation for
redo log files, but redo log files in the range of a hundred megabytes to a
few gigabytes are considered reasonable. Size your online redo log files
according to the amount of redo your system generates. A rough guide is to
switch logs at most once every twenty minutes. Part Number A96533-02

Thanks,

Mark Moynahan

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