fix bug that ExchangeReceiver is not cancelled if exception happens in union/agg block input stream

[windtalker]

Signed-off-by: xufei [email protected]

What problem does this PR solve?

Issue Number: ref #4229

Problem Summary:

some backgrounds:

• For every BlockInputStream, there is a cancel(bool kill) method to cancel the current and all its children input streams.
• In UnionBlockInputStream/ParallelAggregatingBlockInputStream, if some exception happens during processor.process(), it will cancel the BlockInputStream in processor. However, it use silent cancel(false) to do this, which will be ignored by TiRemteBlockInputStream, so the remote_reader in TiRemoteBlockInputStream is not cancelled by cancel(false).
• Due to the implementation of cancel, if a input stream is cancel once, all the subsequent cancels(including cancel(true)) will be ignored.
• MPPTask will use cancel(true) to cancel its BlockInputStream, and all the remote_reader in TiRemoteInputStream

problem
If a input stream is cancelled due to exception in UnionBlockInputStream/ParallelAggregatingBlockInputStream, Cancel query can not cancel this input stream anymore, leaving remote_reader un-cancelled, which may block the MPP query forever.

What is changed and how it works?

In UnionBlockInputStream/ParallelAggregatingBlockInputStream, if some exception happens during processor.process(), use cancel(true) to cancel the BlockInputStream in processor.

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]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• bestwoody
• fuzhe1989

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.

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

[bestwoody]

A little confuse about background "Due to the implementation of cancel, if a input stream is cancel once, all the subsequent cancels(including cancel(true)) will be ignored." . How input stream ensure to be canceled at most call once.

[windtalker]

A little confuse about background "Due to the implementation of cancel, if a input stream is cancel once, all the subsequent cancels(including cancel(true)) will be ignored." . How input stream ensure to be canceled at most call once.

 if (!is_cancelled.compare_exchange_strong(old_val, true, std::memory_order_seq_cst, std::memory_order_relaxed))
        return;

[bestwoody]

is_cancelled

oh, I see

[bestwoody]

LGTM

[fuzhe1989]

why not also do parent.processor.cancel(true) in handleException?

[windtalker]

OK

[windtalker]

/merge

[ti-chi-bot]

@windtalker: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and 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.

If you have any questions about the PR merge process, please refer to pr process.

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]

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

Commit hash: 2feaf00

[sre-bot]

Coverage for changed files

too many lines from llvm-cov, please refer to full report instead

Coverage summary

Functions  MissedFunctions  Executed  Lines   MissedLines  Cover
16923      9503             43.85%    190683  96482        49.40%

full coverage report (for internal network access only)

[windtalker]

/run-all-tests

[sre-bot]

Coverage for changed files

too many lines from llvm-cov, please refer to full report instead

Coverage summary

Functions  MissedFunctions  Executed  Lines   MissedLines  Cover
16923      9502             43.85%    190681  96489        49.40%

full coverage report (for internal network access only)

[sre-bot]

Coverage for changed files

too many lines from llvm-cov, please refer to full report instead

Coverage summary

Functions  MissedFunctions  Executed  Lines   MissedLines  Cover
16923      9503             43.85%    190681  96469        49.41%

full coverage report (for internal network access only)

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #4289.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #4290.