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https://issues.apache.org/jira/browse/LUCENE-2962?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13637548#comment-13637548
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Han Jiang commented on LUCENE-2962:
-----------------------------------

Hmm, as for the average skip length, I think a histogram might be better, I'll 
add this later.
                
> Skip data should be inlined into the postings lists
> ---------------------------------------------------
>
>                 Key: LUCENE-2962
>                 URL: https://issues.apache.org/jira/browse/LUCENE-2962
>             Project: Lucene - Core
>          Issue Type: Improvement
>          Components: core/index
>            Reporter: Michael McCandless
>              Labels: gsoc2013
>         Attachments: proposal.txt
>
>
> Today, we store all skip data as a separate blob at the end of a given term's 
> postings (if that term occurs in enough docs to warrant skip data).
> But this adds overhead during decoding -- we have to seek to a different 
> place for the initial load, we have to init separate readers, we have to seek 
> again while using the lower levels of the skip data, etc.  Also, we have to 
> fully decode all skip information even if we are not going to use it (eg if I 
> only want docIDs, I still must decode position offset and lastPayloadLength).
> If instead we interleaved skip data into the postings file, we could keep it 
> local, and "private" to each file that needs skipping.  This should make it 
> least costly to init and then use the skip data, which'd be a good perf gain 
> for eg PhraseQuery, AndQuery.

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