LGWR tuning

During a previous benchmark I learned that the LGWR will chop writes into chunks of max 1MB. This results in multiple AIO send to the Solaris kernel in quick succession.
The transactions were throttled by 'log file sync' event. Another benchmark will occurr that drives this application to even higher limits. I wonder/expect there is a (hidden) parameter that resets this 1MB limit to something more appropriate.

Any clues how this parameter is called and should be set are very welcome. HInts on side effects that come for free are welcome too :-)

Thanks
Paul

Redo files are on raw devices. A single redo file is mapped on one or more disk arrays (through host based volume management) that each have lots of memory backed up cache. Average write time expected to be in the sub milli second level.

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