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HBase >> mail # user >> difference between major and minor compactions?

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Re: difference between major and minor compactions?
Hi Yun,

Few links:
- http://blog.cloudera.com/blog/2012/06/hbase-io-hfile-input-output/
=> There is a small paragraph about compactions which explain when
they are triggered.
- http://hbase.apache.org/book/regions.arch.html

You are almost right. Only thing is that HBase doesn't know when is
your offpeak, so a major compaction can be triggered anytime if the
minor is promoted to be a major one.


2013/6/22 yun peng <[EMAIL PROTECTED]>:
> Hi, All
> I am asking the different practices of major and minor compaction... My
> current understanding is that minor compaction, triggered automatically,
> usually run along with online query serving (but in background), so that it
> is important to make it as lightweight as possible... to minimise downtime
> (pause time) of online query.
> In contrast, the major compaction is invoked in  offpeak time and usually
> can be assume to have resource exclusively. It may have a different
> performance optimization goal...
> Correct me if wrong, but let me know if HBase does design different
> compaction mechanism this way..?
> Regards,
> Yun