cache hit ratio

[Daniel Beckham]

When someone says "I have a memcached hit ratio of 90%" they are talking 
about a ratio (http://en.wikipedia.org/wiki/Ratio) as it relates to the 
total amount of hits+misses: (get_misses / (get_hits+get_misses)) * 
100.  e.g.  If get_hits returns 900 and get_misses returns 100 we can 
calculate the percentage of hits as related to the whole.  
(900/(100+900)) * 100 = 90% of the memcached requests were hits.  
Incidentally, this is a ratio of 9:1.

-Daniel

B. Keith Murphy wrote:
> Hello all,
>
> I have a question that might be dumb..but I have googled and skimmed 
> through the mailing list not finding an answer.  I have seen various 
> postings saying something along the lines of "I have a memcached hit 
> ratio of 90%".  How is this determined?
>
> Thanks,
>
> Keith
>
> -- 
> B. Keith Murphy
> Database Administrator
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