Fast data parts loading by delaying table startup process #28313
Conversation
This file contains 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
robot-clickhouse
added
the
pr-improvement
|
Could you please explain why does it make data parts loading faster? |
After table starting up, there can be many background merges and fetches and these tasks are quite disk intensive, which contend disk resources against the part loading process. |
|
A test result from production env: 40 min -> 24 min. |
tavplubix
approved these changes
Aug 30, 2021
|
ClickHouse special build check - internal CI issue |
|
@amosbird the iotop result: |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
I hereby agree to the terms of the CLA available at: https://yandex.ru/legal/cla/?lang=en
Changelog category (leave one):
Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):
Speed up data parts loading by delaying table startup process.
Detailed description / Documentation draft:
.