Skip to content

util/chunk: avoid reuse duplicated chunk column in the pool#29809

Merged
ti-chi-bot merged 3 commits intopingcap:masterfrom
tiancaiamao:fix-reuse
Nov 16, 2021
Merged

util/chunk: avoid reuse duplicated chunk column in the pool#29809
ti-chi-bot merged 3 commits intopingcap:masterfrom
tiancaiamao:fix-reuse

Conversation

@tiancaiamao
Copy link
Contributor

What problem does this PR solve?

Issue Number: close #29554 and pingcap/tiflash#3406

Problem Summary:

What is changed and how it works?

Not all the chunk columns are allocated, some are just reference to other columns.

For example, here the second column is the same with the third column, and the fourth column is even a reference to another chunk column:

image

So when we recycle the chunk column for reuse, we must deduplication to avoid introduce the same chunk column to the pool twice. The old array is changed to a map.

Check List

Tests

  • Unit test
  • Integration test
  • Manual test (add detailed scripts or steps below)
  • No code

Side effects

  • Performance regression: Consumes more CPU
  • Performance regression: Consumes more Memory
  • Breaking backward compatibility

Documentation

  • Affects user behaviors
  • Contains syntax changes
  • Contains variable changes
  • Contains experimental features
  • Changes MySQL compatibility

Release note

None

@ti-chi-bot
Copy link
Member

ti-chi-bot commented Nov 15, 2021

[REVIEW NOTIFICATION]

This pull request has been approved by:

  • guo-shaoge
  • lcwangchao

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

The full list of commands accepted by this bot can be found here.

Details

Reviewer can indicate their review by submitting an approval review.
Reviewer can cancel approval by submitting a request changes review.

@ti-chi-bot ti-chi-bot added release-note-none Denotes a PR that doesn't merit a release note. size/M Denotes a PR that changes 30-99 lines, ignoring generated files. labels Nov 15, 2021
@ti-chi-bot ti-chi-bot added the status/LGT1 Indicates that a PR has LGTM 1. label Nov 15, 2021
// freeList is defined as a map, rather than a list, because when recycling chunk
// columns, there could be duplicated one: some of the chunk columns are just the
// reference to the others.
type freeList map[*Column]struct{}
Copy link
Collaborator

Choose a reason for hiding this comment

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

Does this map affects the performance improvements?

Copy link
Contributor Author

Choose a reason for hiding this comment

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

It's allocated once and reused...

@ti-chi-bot ti-chi-bot added status/LGT2 Indicates that a PR has LGTM 2. and removed status/LGT1 Indicates that a PR has LGTM 1. labels Nov 16, 2021
@lcwangchao
Copy link
Collaborator

/merge

@ti-chi-bot
Copy link
Member

This pull request has been accepted and is ready to merge.

DetailsCommit hash: 5ee2866

@ti-chi-bot ti-chi-bot added the status/can-merge Indicates a PR has been approved by a committer. label Nov 16, 2021
@ti-chi-bot
Copy link
Member

@tiancaiamao: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

@ti-chi-bot ti-chi-bot merged commit de60eba into pingcap:master Nov 16, 2021
@tiancaiamao tiancaiamao deleted the fix-reuse branch November 17, 2021 12:01
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

release-note-none Denotes a PR that doesn't merit a release note. size/M Denotes a PR that changes 30-99 lines, ignoring generated files. status/can-merge Indicates a PR has been approved by a committer. status/LGT2 Indicates that a PR has LGTM 2.

Projects

None yet

Development

Successfully merging this pull request may close these issues.

sometimes the stream_agg return wrong results

4 participants