util: fix memory.reArrangeFallback cpu usage (#30414)

[ti-srebot]

cherry-pick #30414 to release-5.0
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# In tidb repo:
git pr https://github.com/pingcap/tidb/pull/34002

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git push [email protected]:ti-srebot/tidb.git pr/34002:release-5.0-b5de819d00be

---

What problem does this PR solve?

Issue Number: close #30353

Problem Summary:

What is changed and how it works?

In my machine, this pr reduce execution time of the sql.
Before this pr: 2.5s+
After this pr: 0.3~0.4s

Profiles:

reArrangeFallback will not use too many cpu

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

Fix the problem of high use of reArrangeFallback cpu.

[ti-chi-bot]

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[ti-chi-bot]

@ti-srebot: This cherry pick PR is for a release branch and has not yet been approved by release team.
Adding the do-not-merge/cherry-pick-not-approved label.

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[ti-srebot]

/run-all-tests

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