Add Facets#getSpecificValues (bulk) and bulk path -> ordinal lookup for taxonomy faceting

[gsmiller]

Description

LUCENE-9476 added the ability to do bulk ordinal -> path lookups, but we have no bulk lookup in the other direction. I think we can find some efficiency gains if we add bulk lookup for paths, which we could then put behind a Facets#getSpecificValues API for retrieving facet values for multiple paths in bulk. There's some nuance down in the depths of MultiTerms, so maybe there's nothing to be gained here, but I think there ought to be (I'll try to look in more detail later, but wanted to open an issue to track the idea in case I forget). A few thoughts:

1. We can seek the terms dictionaries in a single direction if we sort the paths before looking them up.
2. We should be able to reuse postings.

[uschindler]

Hi, the commit causes test failures like this from time to time:

org.apache.lucene.facet.taxonomy.directory.TestDirectoryTaxonomyReader > testGetPathAndOrdinalsRandomMultithreading FAILED
    com.carrotsearch.randomizedtesting.UncaughtExceptionError: Captured an uncaught exception in thread: Thread[id=276, name=Thread-152, state=RUNNABLE, group=TGRP-TestDirectoryTaxonomyReader]

        Caused by:
        java.lang.IllegalArgumentException: bound must be positive
            at __randomizedtesting.SeedInfo.seed([EB36AAC7E6947189]:0)
            at java.base/java.util.Random.nextInt(Random.java:322)
            at randomizedtesting.runner@2.8.1/com.carrotsearch.randomizedtesting.Xoroshiro128PlusRandom.nextInt(Xoroshiro128PlusRandom.java:73)
            at randomizedtesting.runner@2.8.1/com.carrotsearch.randomizedtesting.AssertingRandom.nextInt(AssertingRandom.java:87)
            at org.apache.lucene.facet.taxonomy.directory.TestDirectoryTaxonomyReader.assertGettingPaths(TestDirectoryTaxonomyReader.java:519)
            at org.apache.lucene.facet.taxonomy.directory.TestDirectoryTaxonomyReader$4.run(TestDirectoryTaxonomyReader.java:721)

And hundreds of more threads following. Looks like sometimes the ordinals array is initialized by zero length. The followup random then fail because the upper bound passed to random#nextInt(limit) must be limit>=1.

[mikemccand]

OK fixed @uschindler -- sorry!

[mikemccand]

And thanks @epotyom!

[gsmiller]

Thanks @epotyom! Should we consider a follow up PR that leverages this new bulk lookup by adding something like Facets#getSpecificValues that gets facet values for multiple paths at once? What do you think?

[epotyom]

@gsmiller yes, I'll be working on that now as well as adding benchmark task for getSpecificValues, as was discussed with Mike in #12769 (review) .

[gsmiller]

@epotyom got it, thanks! Didn't see that earlier conversation.

[ChrisHegarty]

Hi,

I'd like to ask a clarifying question as part of the 9.9.0 release manager duties, since this currently-unresolved issue is associated with Milestone 9.9.0.

It's clear that progress has been made on this issue, with the addition of the new TaxonomyReader::getBulkOrdinals method. Is more work planned, or should this issue be closed? It's fine either way, I just want to ensure that we are clear about the targeted release, if any.

[mikemccand]

Thanks @ChrisHegarty -- this one is done.

[epotyom]

@mikemccand , @ChrisHegarty ,

Sorry for confusion, but this issue is not fully done yet. This issue includes:

1. [done] Add TaxonomyReader#getBulkOrdinals method (Add TaxonomyReader#getBulkOrdinals method (#12180) #12769)
2. [in review now] Add Facets#getBulkSpecificValues method which uses getBulkOrdinals to get multiple specific values at once. (Add Facets#getBulkSpecificValues method #12862)
3. [not started yet] Adding performance test task for the new APIs

[mikemccand]

Sorry for confusion, but this issue is not fully done yet

Ahh, thanks @epotyom. Since this issue was partially merged and released in 9.9.0, can you open a new issue for the followon tasks?

[not started yet] Adding performance test task for the new APIs

This would be great to have, but should not block step 2 -- we are free to introduce new APIs without fully knowing their performance characteristics yet.

[epotyom]

@mikemccand ,

can you open a new issue for the followon tasks?

Opened #12919