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From Tatsuya Kawano <tatsuy...@snowcocoa.info>
Subject Re: HBase 0.20.1 on Ubuntu 9.04: master fails to start
Date Thu, 29 Oct 2009 23:54:35 GMT
Hello, Artyom,

> I'll try both:
> 1. Increase RAM capacity
> 2. Decrease heap size
>
> Also I'll try to optimize table structure.

Good luck!

One more thing about the table structure, is channel_products table a
kind of join table in SQL world? If so, you could de-normalize the
table structure and eliminate that table.

Since HBase doesn't provide foreign key index and table join, your
current implementation of looking up the join table results a full
table scan of 3 million records, which will take a few seconds to
complete. If you de-normalize the table structure and eliminate the
join table, the same query could complete in a few milli-seconds and
of course consume much much smaller amount of memory.

So please take a look at HBase FAQ #10 at http://bit.ly/2RyrI3 , as
well as the case studies by Evan Liu at http://bit.ly/1eGU2r . They
will show you how to eliminate the join table.


-- 
Tatsuya Kawano (Mr.)
Tokyo, Japan

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