executor: add CPU padding for chunk.Iterator4Slice

[guo-shaoge]

Signed-off-by: guo-shaoge shaoge1994@163.com

What problem does this PR solve?

Issue Number: close #xxx

Problem Summary: #38741 fix lock contention problem of IndexHashJoin, but looks like there is false sharing problem for HashJoin. So this pr add cpu padding.

What is changed and how it works?

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

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• XuHuaiyu
• wshwsh12

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[guo-shaoge]

/merge

[ti-chi-bot]

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

Commit hash: 8bdf412

[sre-bot]

TiDB MergeCI notify

CI Name	Result	Duration	Compare with Parent commit
idc-jenkins-ci-tidb/integration-ddl-test	🟢 all 6 tests passed	22 min	Existing passed
idc-jenkins-ci/integration-cdc-test	🟢 all 38 tests passed	20 min	Existing passed
idc-jenkins-ci-tidb/common-test	🟢 all 11 tests passed	17 min	Existing passed
idc-jenkins-ci-tidb/integration-common-test	🟢 all 17 tests passed	13 min	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-1	🟢 all 26 tests passed	6 min 33 sec	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-2	🟢 all 28 tests passed	6 min 23 sec	Existing passed
idc-jenkins-ci-tidb/tics-test	🟢 all 1 tests passed	5 min 54 sec	Existing passed
idc-jenkins-ci-tidb/integration-compatibility-test	🟢 all 1 tests passed	3 min 33 sec	Existing passed
idc-jenkins-ci-tidb/mybatis-test	🟢 all 1 tests passed	3 min 4 sec	Existing passed
idc-jenkins-ci-tidb/plugin-test	🟢 build success, plugin test success	4min	Existing passed