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https://issues.apache.org/jira/browse/LUCENE-9378?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17222962#comment-17222962
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Michael Gibney commented on LUCENE-9378:
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{quote}I prefer that BinaryDocValues be simple/fast as it was by default with a 
configurable option to add some compression.
{quote}
+1 for an option to bypass compression, however that's accomplished. To note 
what might be obvious: this change hasn't even fully hit yet in user-land, 
having been introduced in 8.5. Also maybe worth emphasizing that for 
bulk-export cases that access values for all docs in arbitrary order (e.g., 
Solr export handler), iiuc this would result in each block being independently 
decompressed _for each doc in that block_. Not sure whether there are analogous 
tools in elasticsearch (or other) ...

> Configurable compression for BinaryDocValues
> --------------------------------------------
>
>                 Key: LUCENE-9378
>                 URL: https://issues.apache.org/jira/browse/LUCENE-9378
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Viral Gandhi
>            Priority: Minor
>         Attachments: hotspots-v76x.png, hotspots-v76x.png, hotspots-v76x.png, 
> hotspots-v76x.png, hotspots-v76x.png, hotspots-v77x.png, hotspots-v77x.png, 
> hotspots-v77x.png, hotspots-v77x.png, image-2020-06-12-22-17-30-339.png, 
> image-2020-06-12-22-17-53-961.png, image-2020-06-12-22-18-24-527.png, 
> image-2020-06-12-22-18-48-919.png, snapshot-v77x.nps, snapshot-v77x.nps, 
> snapshot-v77x.nps, snapshots-v76x.nps, snapshots-v76x.nps, snapshots-v76x.nps
>
>          Time Spent: 4h 10m
>  Remaining Estimate: 0h
>
> Lucene 8.5.1 includes a change to always [compress 
> BinaryDocValues|https://issues.apache.org/jira/browse/LUCENE-9211]. This 
> caused (~30%) reduction in our red-line QPS (throughput). 
> We think users should be given some way to opt-in for this compression 
> feature instead of always being enabled which can have a substantial query 
> time cost as we saw during our upgrade. [~mikemccand] suggested one possible 
> approach by introducing a *mode* in Lucene80DocValuesFormat (COMPRESSED and 
> UNCOMPRESSED) and allowing users to create a custom Codec subclassing the 
> default Codec and pick the format they want.
> Idea is similar to Lucene50StoredFieldsFormat which has two modes, 
> Mode.BEST_SPEED and Mode.BEST_COMPRESSION.
> Here's related issues for adding benchmark covering BINARY doc values 
> query-time performance - [https://github.com/mikemccand/luceneutil/issues/61]



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