Need help understanding memcached stats

Christopher Schmidt crschmidt at
Mon Feb 12 22:56:23 UTC 2007

On Mon, Feb 12, 2007 at 12:28:17PM -0800, Garth Webb wrote:
> You can look at 'get_hits' and 'get_misses' to get an idea of how your
> cache is doing. These are the number of times a 'get' request tried to
> retrieve something and got it, or found nothing respectively.  In your
> case:
>   100 * 281577/(281577+5381) == 98%
> A 98% hit rate is very good.

Especially since it looks like 5378 of those misses later led to writes,
given the cmd_set being 5378. So, I'd guess that in no case has your
cache ever had a cache miss after writing the data into the cache. This
seems totally unsurprising, since it looks like the size of your cache
(limit_maxbytes) is 256 meg, and the data you're storing in your cache
is only taking up 12735133 bytes, or 12 megs (or so -- I'm not good at
base 2 math in my head :)). 

So, unless I'm reading something wrong, it looks like you can cache
10-20 times as much stuff as you currently are, and still not fill up
the cache. 

Christopher Schmidt
Web Developer

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