Add some logs and adjust the param for split table

[hongyunyan]

What problem does this PR solve?

Issue Number: close #xxx

What is changed and how it works?

1. disable check imbalance to make split more stable
2. frequently check hot spans to make split more timely

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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[ti-chi-bot]

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Notice: To remove the do-not-merge/needs-linked-issue label, please provide the linked issue number on one line in the PR body, for example: Issue Number: close #123 or Issue Number: ref #456.

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lidezhu

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-02-20 03:17:54.052405108 +0000 UTC m=+1104116.448627163: ☑️ agreed by lidezhu.