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From Peter Schuller <>
Subject Re: Calculate memory used for keycache
Date Tue, 15 Mar 2011 18:19:49 GMT
> One additionnal question, I don't really understand what is in the key
> cache. I have a column family with only one key, and the keycache size
> is 118 ... ?

The key cache is basically a hash table mapping row keys to sstable
offsets. It avoids the need to read from the index portion of the
sstable for specific keys that have recently been accessed. (Normally
the index portion is seeked into, a bit of data is streamed from disk,
de-serialized, and used to find the offset for that key).

/ Peter Schuller

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