LOG_BUFFER tuning

In a paper on dbatoolbox.com, Susan Georgson says that the following SQL call should always return zero, and to increase LOG_BUFFER if it isn't zero:

SELECT name, value FROM v$sysstat WHERE name='redo buffer allocation retries';

On an Oracle 7 server suffering performance problems, I've increased LOG_BUFFER to the point that I'm getting approx. 30 of these retries a day.

Is this close enough, or does the value need to be ABSOLUTELY zero?

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  /  cfisher_at_rhadmin.org                 | of good: ever dig, and it will   /
 /   http://rhadmin.org:81               | ever flow."  -Marcus Aurelius   /
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