April 2015
Beginner to intermediate
194 pages
4h 18m
English
Content preview from Hadoop EssentialsBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Compaction
In HBase, the MemStore in Regions creates many HFiles for a Column Family. This large number of files will require more time to read and hence, can impact the read performance. To improve the performance, HBase performs compaction to merge files in order to reduce their number and to keep the data manageable. The compaction process identifies the StoreFiles to merge by running an algorithm which is called compaction policy. There are two types of compactions: minor compactions and major compactions.
The Compaction policy
Compaction policy is the algorithm which can be used to select the StoreFiles for merging. Two policies are possible and the available ones are ExploringCompactionPolicy and RatioBasedCompactionPolicy. To set the policy ...
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.