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https://issues.apache.org/jira/browse/HADOOP-17292?focusedWorklogId=508787&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-508787
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ASF GitHub Bot logged work on HADOOP-17292:
-------------------------------------------

                Author: ASF GitHub Bot
            Created on: 07/Nov/20 18:01
            Start Date: 07/Nov/20 18:01
    Worklog Time Spent: 10m 
      Work Description: viirya commented on pull request #2350:
URL: https://github.com/apache/hadoop/pull/2350#issuecomment-723475628


   > I got a portability issue on bundled snappy .so of snappy-java in 
[xerial/snappy-java#256](https://github.com/xerial/snappy-java/pull/256). It 
could be downside that we can not directly control the portability. While I 
could not find how the bundled lz4 is built yet, it is enough portable since it 
has no dependency on other library?
   
   Thanks for asking. The underlying of lz4-java is lz4 
(https://lz4.github.io/lz4/), I think it is the same as current Hadoop's lz4 
library.
   
   ```
   LZ4 - Fast LZ compression algorithm
      Copyright (C) 2011-present, Yann Collet.
   ...
      You can contact the author at :
       - LZ4 homepage : http://www.lz4.org
       - LZ4 source repository : https://github.com/lz4/lz4
   ```
   
   So I think it should be as portable as before?
   
   BTW, for snappy-java and lz4-java, if no native library for your platform is 
found, it will fallback pure-java implementation. 


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Issue Time Tracking
-------------------

    Worklog Id:     (was: 508787)
    Time Spent: 7h 20m  (was: 7h 10m)

> Using lz4-java in Lz4Codec
> --------------------------
>
>                 Key: HADOOP-17292
>                 URL: https://issues.apache.org/jira/browse/HADOOP-17292
>             Project: Hadoop Common
>          Issue Type: New Feature
>          Components: common
>    Affects Versions: 3.3.0
>            Reporter: L. C. Hsieh
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 7h 20m
>  Remaining Estimate: 0h
>
> In Hadoop, we use native libs for lz4 codec which has several disadvantages:
> It requires native libhadoop to be installed in system LD_LIBRARY_PATH, and 
> they have to be installed separately on each node of the clusters, container 
> images, or local test environments which adds huge complexities from 
> deployment point of view. In some environments, it requires compiling the 
> natives from sources which is non-trivial. Also, this approach is platform 
> dependent; the binary may not work in different platform, so it requires 
> recompilation.
> It requires extra configuration of java.library.path to load the natives, and 
> it results higher application deployment and maintenance cost for users.
> Projects such as Spark use [lz4-java|https://github.com/lz4/lz4-java] which 
> is JNI-based implementation. It contains native binaries in jar file, and it 
> can automatically load the native binaries into JVM from jar without any 
> setup. If a native implementation can not be found for a platform, it can 
> fallback to pure-java implementation of lz4.



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