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https://issues.apache.org/jira/browse/LUCENE-2810?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12970853#action_12970853
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Robert Muir commented on LUCENE-2810:
-------------------------------------

Grant i did read what you wrote, I'm not jumping to conclusions.

bq. And it does belong in Lucene b/c I don't want to have to introduce another 
storage technique.

I don't think that we should add "Compression 2.0" just because of this reason. 
it might simply slow down other users who have high
expectations for compression. This is one of the reasons Compression 1.0 was 
removed right? Lots of users compressing things
and only making things slower and worse.

in any event, its useless to add any compression that doesn't beat what 
filesystems can already do on average.


> Stored Fields Compression
> -------------------------
>
>                 Key: LUCENE-2810
>                 URL: https://issues.apache.org/jira/browse/LUCENE-2810
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: Store
>            Reporter: Grant Ingersoll
>            Assignee: Grant Ingersoll
>
> In some cases (logs, HTML pages w/ boilerplate, etc.), the stored fields for 
> documents contain a lot of redundant information and end up wasting a lot of 
> space across a large collection of documents.  For instance, simply 
> compressing a typical log file often results in > 75% compression rates.  We 
> should explore mechanisms for applying compression across all the documents 
> for a field (or fields) while still maintaining relatively fast lookup (that 
> being said, in most logging applications, fast retrieval of a given event is 
> not always critical.)  For instance, perhaps it is possible to have a part of 
> storage that contains the set of unique values for all the fields and the 
> document field value simply contains a reference (could be as small as a few 
> bits depending on the number of uniq. items) to that value instead of having 
> a full copy.  Extending this, perhaps we can leverage some existing 
> compression capabilities in Java to provide this as well.  
> It may make sense to implement this as a Directory, but it might also make 
> sense as a Codec, if and when we have support for changing storage Codecs.

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