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From Apache Wiki <wikidi...@apache.org>
Subject [Lucene-hadoop Wiki] Trivial Update of "Hbase/PerformanceEvaluation" by stack
Date Thu, 20 Dec 2007 16:43:51 GMT
Dear Wiki user,

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The following page has been changed by stack:
http://wiki.apache.org/lucene-hadoop/Hbase/PerformanceEvaluation

The comment on the change is:
Note on the mapfile test

------------------------------------------------------------------------------
  
  == 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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