feat(reorder): add enbale_reorder as search parameter #1497

LHT129 · 2026-01-05T07:47:16Z

No description provided.

gemini-code-assist · 2026-01-05T07:47:39Z

Summary of Changes

Hello @LHT129, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the search functionality by introducing a new enable_reorder parameter. This parameter provides fine-grained control over whether the reordering step, which typically improves search accuracy, is performed during query execution. By consolidating reorder-related parameters into a common base class and updating algorithm implementations, the change ensures consistent behavior and allows users to optimize for either recall or performance based on their specific needs. New tests confirm the expected behavior when reordering is enabled or disabled.

Highlights

New Search Parameter: Introduced enable_reorder as a search parameter, allowing explicit control over the reordering step in search algorithms.
Parameter Consolidation: Centralized topk_factor and enable_reorder (formerly use_reorder) into the base IndexSearchParameter class, removing them from algorithm-specific parameter classes like HGraphSearchParameters and IVFSearchParameters.
Conditional Reordering Logic: Updated HGraph and IVF search implementations to apply reordering only if both the internal use_reorder_ flag and the new params.enable_reorder are true.
New Test Cases: Added comprehensive test cases for both HGraph and IVF to validate the functionality of disabling reordering and confirm its expected impact on search recall.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	`/gemini review`	Performs a code review for the current pull request in its current state.
Pull Request Summary	`/gemini summary`	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	`/gemini help`	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

gemini-code-assist

Code Review

This pull request introduces a new search parameter enable_reorder to control the reordering step in HGraph and IVF search algorithms, which is a valuable addition for tuning search performance versus accuracy. The implementation is clean, involving refactoring common search parameters into a base class, which improves code structure. The changes are also well-supported by new tests that validate the functionality of the new parameter. My main feedback is to consistently use the && operator instead of the and keyword for logical operations to align with common C++ conventions and enhance code readability.

gemini-code-assist · 2026-01-05T07:59:19Z

src/algorithm/hgraph.cpp

    this->pool_->ReturnOne(vt);

-    if (use_reorder_) {
+    if (use_reorder_ and params.enable_reorder) {


For consistency with common C++ style and to improve readability, it's recommended to use the && operator for logical AND instead of the and keyword.

if (use_reorder_ && params.enable_reorder) {

gemini-code-assist · 2026-01-05T07:59:20Z

src/algorithm/ivf.cpp

    param.search_mode = KNN_SEARCH;
    param.topk = request.topk_;
-    if (use_reorder_) {
+    if (use_reorder_ and param.enable_reorder) {


For consistency with common C++ style and to improve readability, it's recommended to use the && operator for logical AND instead of the and keyword.

Suggested change

if (use_reorder_ and param.enable_reorder) {

if (use_reorder_ && param.enable_reorder) {

gemini-code-assist · 2026-01-05T07:59:20Z

src/algorithm/ivf.cpp

    Statistics stats;
    auto search_result = this->search<KNN_SEARCH>(query, param, stats);
-    if (use_reorder_) {
+    if (use_reorder_ and param.enable_reorder) {


For consistency with common C++ style and to improve readability, it's recommended to use the && operator for logical AND instead of the and keyword.

Suggested change

if (use_reorder_ and param.enable_reorder) {

if (use_reorder_ && param.enable_reorder) {

codecov · 2026-01-05T13:27:57Z

Codecov Report

✅ All modified and coverable lines are covered by tests.

@@           Coverage Diff           @@
##             main    #1497   +/-   ##
=======================================
  Coverage   91.24%   91.25%           
=======================================
  Files         327      327           
  Lines       18977    18980    +3     
=======================================
+ Hits        17316    17320    +4     
+ Misses       1661     1660    -1

Flag	Coverage Δ
cpp	`91.25% <100.00%> (+<0.01%)`	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
common	`85.66% <ø> (ø)`
datacell	`93.56% <ø> (+0.45%)`	⬆️
index	`90.99% <100.00%> (-0.01%)`	⬇️
simd	`100.00% <ø> (ø)`

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 894de68...02b8e2e. Read the comment docs.

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

Signed-off-by: LHT129 <[email protected]>

LHT129 self-assigned this Jan 5, 2026

LHT129 added the kind/feature New feature or request label Jan 5, 2026

LHT129 requested a review from inabao as a code owner January 5, 2026 07:47

LHT129 added the version/0.18 label Jan 5, 2026

LHT129 requested review from ShawnShawnYou, jiaweizone and wxyucs as code owners January 5, 2026 07:47

pull-request-size bot added the size/L label Jan 5, 2026

mergify bot added the module/testing label Jan 5, 2026

gemini-code-assist bot reviewed Jan 5, 2026

View reviewed changes

LHT129 force-pushed the reorder branch 4 times, most recently from 90a22cb to 78d8e89 Compare January 5, 2026 11:42

LHT129 force-pushed the reorder branch 4 times, most recently from 3153008 to 0d51934 Compare January 15, 2026 02:52

feat(reorder): add enbale_reorder as search parameter

02b8e2e

Signed-off-by: LHT129 <[email protected]>

LHT129 force-pushed the reorder branch from 0d51934 to 02b8e2e Compare January 15, 2026 07:21

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

feat(reorder): add enbale_reorder as search parameter #1497

feat(reorder): add enbale_reorder as search parameter #1497

Uh oh!

LHT129 commented Jan 5, 2026

Uh oh!

gemini-code-assist bot commented Jan 5, 2026

Uh oh!

gemini-code-assist bot left a comment

Uh oh!

gemini-code-assist bot Jan 5, 2026

Uh oh!

gemini-code-assist bot Jan 5, 2026

Uh oh!

gemini-code-assist bot Jan 5, 2026

Uh oh!

codecov bot commented Jan 5, 2026 •

edited

Loading

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

	if (use_reorder_ and param.enable_reorder) {
	if (use_reorder_ && param.enable_reorder) {

feat(reorder): add enbale_reorder as search parameter #1497

Are you sure you want to change the base?

feat(reorder): add enbale_reorder as search parameter #1497

Uh oh!

Conversation

LHT129 commented Jan 5, 2026

Uh oh!

gemini-code-assist bot commented Jan 5, 2026

Summary of Changes

Highlights

Footnotes

Uh oh!

gemini-code-assist bot left a comment

Choose a reason for hiding this comment

Code Review

Uh oh!

gemini-code-assist bot Jan 5, 2026

Choose a reason for hiding this comment

Uh oh!

gemini-code-assist bot Jan 5, 2026

Choose a reason for hiding this comment

Uh oh!

gemini-code-assist bot Jan 5, 2026

Choose a reason for hiding this comment

Uh oh!

codecov bot commented Jan 5, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Codecov Report

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

codecov bot commented Jan 5, 2026 •

edited

Loading