Where does HBase store all the row keys?

I am working on hbase. I have some questions:

1. Where does HBase store the row key? Is it in the memory of each region server? O开发者_Python百科r on the disk?

2. If my row keys are extremely very large, what will happen?

Thanks!

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The full row key is stored in every cell, allowing the sparse storage.

That means that the full row will be written for every single row:family:column key. The column names are also stored.

This obviously means that large row/column names will consume a lot of disk space.

A lot of this can be mitigated by using lzo storage: http://wiki.apache.org/hadoop/UsingLzoCompression

Lars George has a very good article about the basic layout of data in hbase(it is a bit old now, but the basic layout is still the same afaik): http://www.larsgeorge.com/2009/10/hbase-architecture-101-storage.html