Fix Faiss byte vector efficient filter bug

[naveentatikonda]

Description

Resolves a bug which is running into NullPointerException when we are computing P * Dimension <= Max_distance_computations for faiss efficient filters using byte vectors.

This is a short term solution, created a separate github issue #2447 to refactor and handle different vector datatypes without branching, to improve the code quality and avoid running into bugs like these.

Related Issues

Resolves #2310

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

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[VijayanB]

Can we also cover benchmark to verify that whether one threshold is good enough or do we need different threshold per vector data type as long term fix?

[naveentatikonda]

Can we also cover benchmark to verify that whether one threshold is good enough or do we need different threshold per vector data type as long term fix?

What threshold are you referring to ?

[VijayanB]

Can we also cover benchmark to verify that whether one threshold is good enough or do we need different threshold per vector data type as long term fix?

What threshold are you referring to ?

I think it is added as TODO just before your code change

[martin-gaievski]

looks good, thank you

[opensearch-trigger-bot]

The backport to main failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-main main
# Navigate to the new working tree
cd .worktrees/backport-main
# Create a new branch
git switch --create backport/backport-2448-to-main
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 02fdd70f1a10e9faa290c5a92d2c2dc5db3fe31e
# Push it to GitHub
git push --set-upstream origin backport/backport-2448-to-main
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-main

Then, create a pull request where the base branch is main and the compare/head branch is backport/backport-2448-to-main.