On 5/6/10 3:26 PM, Stu Hood wrote:
Ian: I think that as get_range_slice gets faster, the approach that Mark was
heading toward may be considerably more efficient than reading the old value in
the OutputFormat.
Interesting, I'm trying to understand the performance impact of the
different ways to do this. Under Mark's approach, the prior values are
pulled out of Cassandra in the mapper in bulk, then merged and written
back to Cassandra in the reducer; the get_range_slice is faster than the
individual row fetches that my approach does in the reducer. Is that
what you mean or are you referring to something else?
thanks!
-Ian
--
Ian Kallen
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