Skip to content

Add IVF sampled ADC start-point router - #1279

Draft
xwj-ox wants to merge 1 commit into
mainfrom
codex/ivf-sampled-adc-router
Draft

Add IVF sampled ADC start-point router#1279
xwj-ox wants to merge 1 commit into
mainfrom
codex/ivf-sampled-adc-router

Conversation

@xwj-ox

@xwj-ox xwj-ox commented Jul 28, 2026

Copy link
Copy Markdown

Summary

  • add a focused IVF posting-list sampled ADC start-point router for disk search
  • build and load an IVF+PQ router artifact with centroids, posting offsets, posting IDs, and fallback medoid
  • route queries by probing IVF cells, strided sampling posting lists, scoring sampled IDs with existing global PQ ADC, and seeding disk Vamana traversal
  • wire benchmark build/search config for ivf_pq_router_build and start_point_router
  • include bilingual RFC for the sampled ADC design

Scope

This intentionally excludes residual PQ, PQ sidecars, block routers, hierarchy, posting-order PQ layout, mmap artifact loading, and experiment result artifacts.

Validation

  • cargo fmt --all --check
  • cargo test -p diskann-disk ivf -- --nocapture
  • cargo test -p diskann-benchmark --features disk-index ivf_pq -- --nocapture
  • cargo clippy -p diskann-disk --tests -- -D warnings
  • cargo clippy -p diskann-benchmark --features disk-index --bins --tests -- -D warnings

Copilot AI review requested due to automatic review settings July 28, 2026 07:22
@microsoft-github-policy-service

Copy link
Copy Markdown

@xwj-ox please read the following Contributor License Agreement(CLA). If you agree with the CLA, please reply with the following information.

@microsoft-github-policy-service agree [company="{your company}"]

Options:

  • (default - no company specified) I have sole ownership of intellectual property rights to my Submissions and I am not making Submissions in the course of work for my employer.
@microsoft-github-policy-service agree
  • (when company given) I am making Submissions in the course of work for my employer (or my employer has intellectual property rights in my Submissions by contract or applicable law). I have permission from my employer to make Submissions and enter into this Agreement on behalf of my employer. By signing below, the defined term “You” includes me and my employer.
@microsoft-github-policy-service agree company="Microsoft"
Contributor License Agreement

Contribution License Agreement

This Contribution License Agreement (“Agreement”) is agreed to by the party signing below (“You”),
and conveys certain license rights to Microsoft Corporation and its affiliates (“Microsoft”) for Your
contributions to Microsoft open source projects. This Agreement is effective as of the latest signature
date below.

  1. Definitions.
    “Code” means the computer software code, whether in human-readable or machine-executable form,
    that is delivered by You to Microsoft under this Agreement.
    “Project” means any of the projects owned or managed by Microsoft and offered under a license
    approved by the Open Source Initiative (www.opensource.org).
    “Submit” is the act of uploading, submitting, transmitting, or distributing code or other content to any
    Project, including but not limited to communication on electronic mailing lists, source code control
    systems, and issue tracking systems that are managed by, or on behalf of, the Project for the purpose of
    discussing and improving that Project, but excluding communication that is conspicuously marked or
    otherwise designated in writing by You as “Not a Submission.”
    “Submission” means the Code and any other copyrightable material Submitted by You, including any
    associated comments and documentation.
  2. Your Submission. You must agree to the terms of this Agreement before making a Submission to any
    Project. This Agreement covers any and all Submissions that You, now or in the future (except as
    described in Section 4 below), Submit to any Project.
  3. Originality of Work. You represent that each of Your Submissions is entirely Your original work.
    Should You wish to Submit materials that are not Your original work, You may Submit them separately
    to the Project if You (a) retain all copyright and license information that was in the materials as You
    received them, (b) in the description accompanying Your Submission, include the phrase “Submission
    containing materials of a third party:” followed by the names of the third party and any licenses or other
    restrictions of which You are aware, and (c) follow any other instructions in the Project’s written
    guidelines concerning Submissions.
  4. Your Employer. References to “employer” in this Agreement include Your employer or anyone else
    for whom You are acting in making Your Submission, e.g. as a contractor, vendor, or agent. If Your
    Submission is made in the course of Your work for an employer or Your employer has intellectual
    property rights in Your Submission by contract or applicable law, You must secure permission from Your
    employer to make the Submission before signing this Agreement. In that case, the term “You” in this
    Agreement will refer to You and the employer collectively. If You change employers in the future and
    desire to Submit additional Submissions for the new employer, then You agree to sign a new Agreement
    and secure permission from the new employer before Submitting those Submissions.
  5. Licenses.
  • Copyright License. You grant Microsoft, and those who receive the Submission directly or
    indirectly from Microsoft, a perpetual, worldwide, non-exclusive, royalty-free, irrevocable license in the
    Submission to reproduce, prepare derivative works of, publicly display, publicly perform, and distribute
    the Submission and such derivative works, and to sublicense any or all of the foregoing rights to third
    parties.
  • Patent License. You grant Microsoft, and those who receive the Submission directly or
    indirectly from Microsoft, a perpetual, worldwide, non-exclusive, royalty-free, irrevocable license under
    Your patent claims that are necessarily infringed by the Submission or the combination of the
    Submission with the Project to which it was Submitted to make, have made, use, offer to sell, sell and
    import or otherwise dispose of the Submission alone or with the Project.
  • Other Rights Reserved. Each party reserves all rights not expressly granted in this Agreement.
    No additional licenses or rights whatsoever (including, without limitation, any implied licenses) are
    granted by implication, exhaustion, estoppel or otherwise.
  1. Representations and Warranties. You represent that You are legally entitled to grant the above
    licenses. You represent that each of Your Submissions is entirely Your original work (except as You may
    have disclosed under Section 3). You represent that You have secured permission from Your employer to
    make the Submission in cases where Your Submission is made in the course of Your work for Your
    employer or Your employer has intellectual property rights in Your Submission by contract or applicable
    law. If You are signing this Agreement on behalf of Your employer, You represent and warrant that You
    have the necessary authority to bind the listed employer to the obligations contained in this Agreement.
    You are not expected to provide support for Your Submission, unless You choose to do so. UNLESS
    REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING, AND EXCEPT FOR THE WARRANTIES
    EXPRESSLY STATED IN SECTIONS 3, 4, AND 6, THE SUBMISSION PROVIDED UNDER THIS AGREEMENT IS
    PROVIDED WITHOUT WARRANTY OF ANY KIND, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY OF
    NONINFRINGEMENT, MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE.
  2. Notice to Microsoft. You agree to notify Microsoft in writing of any facts or circumstances of which
    You later become aware that would make Your representations in this Agreement inaccurate in any
    respect.
  3. Information about Submissions. You agree that contributions to Projects and information about
    contributions may be maintained indefinitely and disclosed publicly, including Your name and other
    information that You submit with Your Submission.
  4. Governing Law/Jurisdiction. This Agreement is governed by the laws of the State of Washington, and
    the parties consent to exclusive jurisdiction and venue in the federal courts sitting in King County,
    Washington, unless no federal subject matter jurisdiction exists, in which case the parties consent to
    exclusive jurisdiction and venue in the Superior Court of King County, Washington. The parties waive all
    defenses of lack of personal jurisdiction and forum non-conveniens.
  5. Entire Agreement/Assignment. This Agreement is the entire agreement between the parties, and
    supersedes any and all prior agreements, understandings or communications, written or oral, between
    the parties relating to the subject matter hereof. This Agreement may be assigned by Microsoft.

Copilot AI left a comment

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Pull request overview

This PR introduces an IVF+PQ posting-list sampled ADC start-point router for DiskANN disk search, including artifact build/load support, query-time routing to seed disk Vamana traversal, and benchmark plumbing to configure and report router metrics. It also adds a bilingual RFC documenting the design and experimental operating points.

Changes:

  • Add IVF+PQ router artifact format + builder (centroids + posting IDs + offsets + optional fallback medoid) and query-time routing integration for disk search.
  • Extend disk search statistics and benchmark reporting to include router time and sampled-ADC diagnostics.
  • Add benchmark configuration schema for ivf_pq_router_build and start_point_router, plus RFC documentation (EN/ZH).

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.

Show a summary per file
File Description
rfcs/00001-ivf-pq-posting-list-sampled-adc-router.zh.md Chinese RFC describing sampled ADC router design, metrics, and rollout plan
rfcs/00001-ivf-pq-posting-list-sampled-adc-router.en.md English RFC describing sampled ADC router design, metrics, and rollout plan
diskann-disk/src/utils/statistics.rs Adds router timing and diagnostic counters to QueryStatistics
diskann-disk/src/search/start_point_router.rs Introduces StartPointRouter enum wrapper for query-time routing
diskann-disk/src/search/provider/disk_provider.rs Integrates router into disk search path; records router stats; adds routing helpers + unit tests
diskann-disk/src/search/mod.rs Exposes new ivf_pq_router and start_point_router modules
diskann-disk/src/search/ivf_pq_router.rs Implements IVF router artifact build/serialize/deserialize and query-time router parameters
diskann-benchmark/src/inputs/disk.rs Adds JSON config for router artifact build and start-point router selection
diskann-benchmark/src/disk_index/search.rs Loads router artifacts, passes router into disk searcher, and reports new router metrics
diskann-benchmark/src/disk_index/build.rs Builds IVF+PQ router artifacts during benchmark disk-index build step

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

Comment on lines +390 to +392
if data.len() != num_points * dim {
return Err(index_error("data length must equal num_points * dim"));
}
Comment on lines +354 to +365
let mut centroids = vec![0.0; num_centroids * dim];
for value in &mut centroids {
*value = reader.read_f32::<LittleEndian>()?;
}
let mut offsets = vec![0usize; num_centroids + 1];
for offset in &mut offsets {
*offset = usize::try_from(reader.read_u64::<LittleEndian>()?)?;
}
let mut posting_ids = vec![0u32; num_postings];
for id in &mut posting_ids {
*id = reader.read_u32::<LittleEndian>()?;
}
Comment on lines 1516 to 1518
query_stats.cpu_time_us = query_stats.total_execution_time_us
- query_stats.io_time_us
- query_stats.query_pq_preprocess_time_us;
| Parameter | Value |
|---|---:|
| IVF cells | 2048 |
| load mode | mmap |
| 参数 | 值 |
|---|---:|
| IVF cells | 2048 |
| load mode | mmap |
@codecov-commenter

codecov-commenter commented Jul 28, 2026

Copy link
Copy Markdown

Codecov Report

❌ Patch coverage is 65.64246% with 246 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.31%. Comparing base (e197b43) to head (200b6f7).

Files with missing lines Patch % Lines
diskann-disk/src/search/ivf_pq_router.rs 67.62% 146 Missing ⚠️
diskann-disk/src/search/provider/disk_provider.rs 65.21% 88 Missing ⚠️
diskann-benchmark/src/inputs/disk.rs 0.00% 8 Missing ⚠️
diskann-disk/src/search/start_point_router.rs 0.00% 4 Missing ⚠️
Additional details and impacted files

Impacted file tree graph

@@            Coverage Diff             @@
##             main    #1279      +/-   ##
==========================================
- Coverage   91.50%   91.31%   -0.20%     
==========================================
  Files         497      499       +2     
  Lines       95524    96230     +706     
==========================================
+ Hits        87411    87874     +463     
- Misses       8113     8356     +243     
Flag Coverage Δ
miri 91.31% <65.64%> (-0.20%) ⬇️
unittests 91.28% <65.64%> (-0.19%) ⬇️

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

Files with missing lines Coverage Δ
diskann-disk/src/utils/statistics.rs 100.00% <ø> (ø)
diskann-disk/src/search/start_point_router.rs 0.00% <0.00%> (ø)
diskann-benchmark/src/inputs/disk.rs 1.41% <0.00%> (-0.03%) ⬇️
diskann-disk/src/search/provider/disk_provider.rs 88.94% <65.21%> (-4.98%) ⬇️
diskann-disk/src/search/ivf_pq_router.rs 67.62% <67.62%> (ø)

... and 1 file with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

4 participants