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https://issues.apache.org/jira/browse/LUCENE-4584?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13508270#comment-13508270
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Adrien Grand commented on LUCENE-4584:
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bq. You wouldn't need static files if you compared output lengths
Even the output length depends on the endianess: LZ4 uses a hash table without
collision resolution (it maps hash -> last offset that produced this hash) to
find matchs of 4 consecutive bytes in the input bytes, and this hash function
is not endian-neutral (it interprets the 4 bytes as an 32-bits int, multiplies
it by a prime number and keeps the 12 first bits (13 if there are less than
2^16 input bytes)), so the collisions won't be the same depending on the
endianess and LZ4 won't find the same matchs.
> Compare the LZ4 implementation in Lucene against the original impl
> ------------------------------------------------------------------
>
> Key: LUCENE-4584
> URL: https://issues.apache.org/jira/browse/LUCENE-4584
> Project: Lucene - Core
> Issue Type: Task
> Reporter: Adrien Grand
> Assignee: Adrien Grand
> Fix For: 4.1
>
>
> We should add tests to make sure that the LZ4 impl in Lucene compresses data
> the exact same way as the original impl.
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