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using the mysql workbench administrator - my key efficiency is at 99.97% i have read about adding 'key_cache_size=100M' to my.cnf and increasing it as needed

is this the correct fix for the problem? im runing server 5.5.11 on server 2008 r2 , 24gb ram


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up vote 6 down vote accepted

That's actually remarkably good - the higher the better.

The MySQL performance is good if the value of Key Read Efficiency is 90 percent and above

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oh well that saves me a dramatic headache - i was reading this and wasn't sure… – Jeff May 4 '11 at 18:36
here is another question for you, how high is the query cache hitrate supposed to be? mine is at 42.88% – Jeff May 4 '11 at 18:38
The cache hit rate depends highly on the application running against the DB. If you control the application, you should be able to get a very high hit rate. If you don't, (and it is poorly written), you can expect some really low values. – Ryaner May 4 '11 at 18:44
That's nothing to worry about if I remember correctly. You can read on about that on – Eduardo Ivanec May 4 '11 at 18:47
I'm not expert on this, but in my opinion a good although very basic methodology for cache sizing (specially when the problem is so relative to the app) seems to be: increase it, for example 2x, and see how much the metric you're analizing improves. – Eduardo Ivanec May 4 '11 at 18:52

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