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From gabriele renzi <rff....@gmail.com>
Subject Re: OOM Exception
Date Sun, 13 Dec 2009 20:20:43 GMT
On Sun, Dec 13, 2009 at 7:28 PM, Stu Hood <stuart.hood@rackspace.com> wrote:
> With 248G per box, you probably have slightly more than 1/2 billion items?
>
> One current implementation detail in Cassandra is that it loads 128th of the index into
memory for faster lookups. This means you might have something like 4.5 million keys in memory
at the moment.
>
> The '128' value is a constant at SSTable.INDEX_INTERVAL. You should be able to recompile
with '1024' to allow for an 8 times larger database, but understand that this will have a
negative effect on your read performance.


Is there a reason for having this as an hardcoded value instead of
configuration value?
It seems to me that it is a kind of lookup time/memory usage tradeoff
threshold that could be tweaked by users, or is there a reason to not
allow it?

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