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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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