coprocessor: split ranges if the slice is too big #7454
Merged
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
winoros
added
type/enhancement
coocood
reviewed
Aug 22, 2018
store/tikv/coprocessor.go
Outdated
| cmdType: cmdType, | ||
| }) | ||
| rLen := ranges.len() | ||
| for i := 0; i < rLen; { |
There was a problem hiding this comment.
Need to add comments about why slice the task by range.
|
/run-all-tests |
zz-jason
reviewed
Aug 22, 2018
store/tikv/coprocessor.go
Outdated
| @@ -235,6 +236,8 @@ func (r *copRanges) split(key []byte) (*copRanges, *copRanges) { | |||
| return r.slice(0, n), r.slice(n, r.len()) | |||
| } | |||
|
|
|||
| const rangesPerTask = 25000 | |||
There was a problem hiding this comment.
Better to add some comment about what this value is used to do, why need it, why set it to this value.
coocood
reviewed
Aug 22, 2018
store/tikv/coprocessor.go
Outdated
| respChan: make(chan *copResponse, 1), | ||
| cmdType: cmdType, | ||
| }) | ||
| // etcd will return error if the message is too large. So we need to limit the length of the ranges slice |
|
LGTM |
coocood
approved these changes
Aug 22, 2018
zz-jason
approved these changes
Aug 22, 2018
coocood
added
status/LGT2
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Outdated suggestions cannot be applied.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.
What problem does this PR solve?
This PR aims to solve the issue that the TiKV timeout error is caused by the too large range in one request.
What is changed and how it works?
According to @coocood 's advice, split the range in one region when building
copTask. So we won't send a message that is too large.Check List
Tests
select count(*) from t where key in (800k constant list).