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From Apache Wiki <wikidi...@apache.org>
Subject [Cassandra Wiki] Update of "StorageConfiguration" by JonHermes
Date Wed, 01 Sep 2010 19:38:07 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Cassandra Wiki" for change notification.

The "StorageConfiguration" page has been changed by JonHermes.
http://wiki.apache.org/cassandra/StorageConfiguration?action=diff&rev1=43&rev2=44

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   * '''keys_cached''' and '''rows_cached'''
  
- Determines how many keys and rows to cache. The values can either be an absolute value or
a double between 0 and 1 (inclusive on both ends).
+ Determines how many keys and rows to cache. The values can either be an absolute value or
a double between 0 and 1 (inclusive on both ends) denoting what fraction should be cached.
  
  Each key cache hit saves 1 seek and each row cache hit saves 2 seeks at the minimum, sometimes
more. The key cache is fairly tiny for the amount of time it saves, so it's worthwhile to
use it at large numbers all the way up to 1.0 (all keys cached). The row cache saves even
more time, but must store the whole values of its rows, so it is extremely space-intensive.
It's best to only use the row cache if you have hot rows or static rows.
  

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