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From A J <s5a...@gmail.com>
Subject Single column read latency
Date Thu, 08 Mar 2012 20:38:23 GMT
Hello,
In a CF I have with valueless columns and column-name type being
integer, I am seeing latency in the order of 80-90ms to retrieve a
single column from a row containing 50K columns. It is just a single
node db on a single box.
Another row with 20K columns in the same CF, still has the latency
around 30ms to get to a single column.

Example in pycassa, for a row with 50K columns:
t1 = time.time()
cf1.get(5011,columns=[90006111])
t2 = time.time() - t1
print  int(t2*1000),'ms'

gives 82 ms

Any idea what could be causing the latency to be so high ? That too
after ensuring that the row_cache is large enough to contain all the
rows and all the rows are pre-fetched.

Thanks.

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