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http://wiki.apache.org/lucene-hadoop/Hbase/PerformanceEvaluation

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Note on the mapfile test

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  == HBase TRUNK 12/19/2007, r605675 ==
  
- Below are numbers for version r605675, 12/19/2007.  Looks like writing got a 
bit better -- probably because of recent lock refactoring -- but reading speed 
has almost halved.  I'd have expected the read speeds to also have doubled but 
I'd guess there is still a HADOOP-2434 like issue over in the datanode.  I've 
also added numbers for sequential writes, random and next ('scan') reads into 
and out of a single HDFS mapfile for comparison.  Going by current numbers, 
pure mapfile writes are slower than the numbers google posted in initial 
bigtable paper and reads just a bit faster (except when scanning).  GFS must be 
fast.
+ Below are numbers for version r605675, 12/19/2007.  Looks like writing got a 
bit better -- probably because of recent lock refactoring -- but reading speed 
has almost halved.  I'd have expected the read speeds to also have doubled but 
I'd guess there is still a HADOOP-2434 like issue over in the datanode.
+ 
+ I've also added numbers for sequential writes, random and next ('scan') reads 
into and out of a single *open* HDFS mapfile for comparison: i.e. random 
reading, we are not opening the file each time and the mapfile index is loaded 
into memory.  Going by current numbers, pure mapfile writes are slower than the 
numbers google posted in initial bigtable paper and reads just a bit faster 
(except when scanning).  GFS must be fast.
  
  ||<rowbgcolor="#ececec">Experiment 
Run||HBase20070708||HBase20070916||0.15.0||20071219||mapfile||!BigTable||
  ||random reads ||68||272||264||167||1718||1212||

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