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This article mainly introduces "how to use Hbase Release". In daily operation, I believe many people have doubts about how to use Hbase Release. The editor consulted all kinds of materials and sorted out simple and easy-to-use operation methods. I hope it will be helpful to answer the doubts about "how to use Hbase Release". Next, please follow the editor to study!

1: download:

Hbase Releases

2: currently our stable version is: The 0.98.x series

The download interface is as follows:

Select a stable version of Stable to download:

Due to the current two major branches of hbase and hadoo, a matching between versions is required.

Hadoop itself has been updated to the latest second generation of hadoop.

A typical download address is as follows:

Http://mirrors.cnnic.cn/apache/hadoop/common/stable/

、

The currently selected version of hadoop2 is hadoop-2.5.1.tar.gz.

Currently installed is the community version of hadoop2 + hbase0.98. If you want to install the CHD CLouder version of hadoop + hbase, please refer to another blog post, CDH hadoop series

In the latest Hbase release, the following new features have been introduced:

Performance dependent

Read cache improvement: HDFS stores pictures and checksum in different block, so every time we read, we need to do two disk operations (once to read the data file and once to read the file where the checksum is located). In the HBASE-5074 proposal, the idea of storing checksum in the block cache is put forward. In version 0.94, this feature is enabled by default.

Read file optimization: prior to version 0.94, if a column family corresponds to multiple StoreFile, HBase will read data from each StoreFile and merge it, even if the data we need exists in the most recent data file. In the HBASE-4465 proposal, an optimization called Lazy Seek is proposed. By first reading the data in the recent StoreFile, and then seeing whether other StoreFile have operations after the data operation time, if not, the StoreFile will not be read. This greatly reduces the reading of StoreFile, which is enabled by default.

WAL file optimization: WAL means Write Ahead Log. HBase writes WAL files first in every write operation. Usually, the writing speed of WAL files directly affects the overall data throughput of HBase. The WAL file is also synchronized to multiple data nodes based on configuration. In the proposal HBASE-4608, the idea of compressing Hlog data is mentioned. The synchronized log files are smaller and can be synchronized faster among data nodes, thus achieving higher data throughput. At present, this optimization is also enabled by default.

New features

Emergency Box tool enhancements: the original HBck tool has been enhanced to provide fixes for orphan region, region holes, and overlapping region. See proposal HBASE-5128: "Uber hbck".

Simplify Region Size setup: it is usually difficult to set up a region size and many other factors need to be considered. In version 0.94, the region size is formulated by dynamic algorithm according to the method of proposal HBASE-4365.

More complete transaction support: previously, Hbase provided row-level transactions, but each transaction could only perform one write operation, such as performing a series of Put,Delete operations sequentially, so these operations were separate transactions and not atomically executed as a whole. In version 0.94, Put and Delete can be executed atomically together in the same transaction. See proposal HBASE-3584.

In fact, the above are just some big improvements. This version has made a total of 140 enhancements and fixed 180 bug. In your installation package, or in the official release record.

At this point, the study on "how to use Hbase Release" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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