https://www.quora.com/How-does-the-Log-Structured-Merge-Tree-work
http://blog.cloudera.com/blog/2012/06/hbase-io-hfile-input-output/
http://blog.cloudera.com/blog/2012/06/hbase-write-path/
http://paperhub.s3.amazonaws.com/18e91eb4db2114a06ea614f0384f2784.pdf
http://stackoverflow.com/questions/13762992/log-structured-merge-tree-in-hbase
http://www.eecs.harvard.edu/~margo/cs165/papers/gp-lsm.pdf
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.44.2782&rep=rep1&type=pdf
http://www.cs.umb.edu/~poneil/lsmtree.pdf
http://www.cnblogs.com/siegfang/archive/2013/01/12/lsm-tree.html
http://www.cnblogs.com/haippy/archive/2012/01/14/2322207.html
http://www.eecs.harvard.edu/~margo/cs165/papers/gp-lsm.pdf
http://www.open-open.com/lib/view/open1424916275249.html
https://www.quora.com/How-does-the-Log-Structured-Merge-Tree-work
http://www.bzero.se/ldapd/btree.html