Repository navigation
docs: clarify common sub-DAG sharing terminology - #558
Merged
Merged
Conversation
zzylol
commented
Oct 3, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Why
Make the terminology used in #537 explicit in the design and developer docs.
Before this PR: CSE and summary sharing were described without a consistent definition of sub-DAG sharing.
After this PR: the docs define sub-DAG sharing as multiple consumers referencing one operator and its upstream dependencies, and common sub-DAG sharing as CSE deduplication of eligible, structurally identical computations. For example, two estimates can reference the same summary producer. Physical planning determines execution/materialization, and differing execution phases can require separate instances.
Defines the terminology in the planner-layering proposal and CSE cost decision. The mapping architecture guide links to the corresponding planner-layering section. Per review, the added paragraph in the operator-sharing proposal is removed.
Validation: reviewed the documentation diff;
git diff --checkpasses. Documentation only.