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https://issues.apache.org/jira/browse/AVRO-1282?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13638813#comment-13638813
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Scott Carey commented on AVRO-1282:
-----------------------------------

A related issue is what happens when you run under a security manager and 
Unsafe.getUnsafe() does not work.  The examples from the snappy library as well 
as the one that Holger referenced: 
http://code.google.com/p/guava-libraries/source/browse/guava/src/com/google/common/cache/Striped64.java#317
from guava work around the security manager in some cases with reflection.  In 
others, getUnsafe will still fail with a RuntimeException or class not found 
error, which can be caught and the reflection based implementation used 
instead. 

                
> Make use of the sun.misc.Unsafe class during serialization if a JDK supports 
> it
> -------------------------------------------------------------------------------
>
>                 Key: AVRO-1282
>                 URL: https://issues.apache.org/jira/browse/AVRO-1282
>             Project: Avro
>          Issue Type: Improvement
>          Components: java
>    Affects Versions: 1.7.4
>            Reporter: Leo Romanoff
>            Priority: Minor
>         Attachments: avro-1282-v1.patch, avro-1282-v2.patch, 
> avro-1282-v3.patch, avro-1282-v4.patch, avro-1282-v5.patch, avro-1282-v6.patch
>
>
> Unsafe can be used to significantly speed up serialization process, if a JDK 
> implementation supports java.misc.Unsafe properly. Most JDKs running on PCs 
> support it. Some platforms like Android lack a proper support for Unsafe yet.
> There are two possibilities to use Unsafe for serialization:
> 1) Very quick access to the fields of objects. It is way faster than with the 
> reflection-based approach using Field.get/set
> 2) Input and Output streams can be using Unsafe to perform very quick 
> input/output.
>  
> 3) More over, Unsafe makes it possible to serialize to/deserialize from 
> off-heap memory directly and very quickly, without any intermediate buffers 
> allocated on heap. There is virtually no overhead compared to the usual byte 
> arrays.

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