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https://issues.apache.org/jira/browse/LUCENE-4509?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13488389#comment-13488389
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Robert Muir commented on LUCENE-4509:
-------------------------------------

Do we know whats happening with the recent test fail?
{noformat}
ant test  -Dtestcase=TestCompressingStoredFieldsFormat 
-Dtests.method=testBigDocuments -Dtests.seed=37812FE503010D20 
-Dtests.multiplier=3 -Dtests.nightly=true -Dtests.slow=true 
-Dtests.linedocsfile=/home/hudson/lucene-data/enwiki.random.lines.txt 
-Dtests.locale=es_PR -Dtests.timezone=America/Sitka 
{noformat}
                
> Make CompressingStoredFieldsFormat the new default StoredFieldsFormat impl
> --------------------------------------------------------------------------
>
>                 Key: LUCENE-4509
>                 URL: https://issues.apache.org/jira/browse/LUCENE-4509
>             Project: Lucene - Core
>          Issue Type: Wish
>          Components: core/store
>            Reporter: Adrien Grand
>            Assignee: Adrien Grand
>            Priority: Minor
>         Attachments: LUCENE-4509.patch
>
>
> What would you think of making CompressingStoredFieldsFormat the new default 
> StoredFieldsFormat?
> Stored fields compression has many benefitsĀ :
>  - it makes the I/O cache work for us,
>  - file-based index replication/backup becomes cheaper.
> Things to know:
>  - even with incompressible data, there is less than 0.5% overhead with LZ4,
>  - LZ4 compression requires ~ 16kB of memory and LZ4 HC compression requires 
> ~ 256kB,
>  - LZ4 uncompression has almost no memory overhead,
>  - on my low-end laptop, the LZ4 impl in Lucene uncompresses at ~ 300mB/s.
> I think we could use the same default parameters as in CompressingCodec :
>  - LZ4 compression,
>  - in-memory stored fields index that is very memory-efficient (less than 12 
> bytes per block of compressed docs) and uses binary search to locate 
> documents in the fields data file,
>  - 16 kB blocks (small enough so that there is no major slow down when the 
> whole index would fit into the I/O cache anyway, and large enough to provide 
> interesting compression ratiosĀ ; for example Robert got a 0.35 compression 
> ratio with the geonames.org database).
> Any concerns?

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