test: modify fail_over_ddl_mix integration test

[wk989898]

What problem does this PR solve?

Issue Number: ref #442

What is changed and how it works?

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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[gemini-code-assist]

Summary of Changes

Hello @wk989898, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request modifies an existing integration test by adjusting a timing parameter. The change extends a sleep duration within the fail_over_ddl_mix test, likely to enhance its stability and reliability by providing more time for asynchronous operations to complete before subsequent test assertions.

Highlights

• Integration Test Modification: The fail_over_ddl_mix integration test script (run.sh) has been updated.
• Increased Sleep Duration: A sleep command within the test script was extended from 30 seconds to 60 seconds.

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[gemini-code-assist]

Code Review

This pull request modifies an integration test by increasing a sleep duration, likely to fix a flaky test. While this might resolve an immediate issue, I've suggested a more robust approach that involves polling for a specific condition (changefeed checkpoint advancement) instead of a fixed wait. This will make the test more reliable and potentially more efficient.

[gemini-code-assist]

Increasing the sleep time can make the test more stable, but it's not a robust solution and it slows down the test execution. A better approach is to actively wait for the changefeed to replicate all data up to the point where DMLs were stopped. This can be achieved by polling the changefeed's checkpoint TSO until it surpasses the TSO captured after killing the DML processes. This makes the test both more reliable and potentially faster, as it waits only as long as necessary.

Suggested change

	sleep 60
	# Wait for replication to catch up before checking diff.
	# This is more robust than a fixed sleep time.
	current_tso=$(run_cdc_cli_tso_query ${UP_PD_HOST_1} ${UP_PD_PORT_1})
	i=0
	while [ $i -lt 60 ]; do
	checkpoint_tso=$(cdc_cli_changefeed query -c "test" 2>&1 | grep -v "Command to ticdc" | jq '.checkpoint_tso')
	if [[ "$checkpoint_tso" != "null" && "$checkpoint_tso" -ge "$current_tso" ]]; then
	echo "Changefeed checkpoint ($checkpoint_tso) has passed target TSO ($current_tso)."
	break
	fi
	sleep 2
	i=$((i+1))
	done
	if [ $i -ge 60 ]; then
	echo "Timed out waiting for changefeed checkpoint to advance."
	cdc_cli_changefeed query -c "test"
	exit 1
	fi

[wlwilliamx]

not the root cause, we need to find the root cause or a better way to avoid it failed

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hongyunyan

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-12-02 07:11:45.998583619 +0000 UTC m=+333850.812361191: ☑️ agreed by wlwilliamx.
• 2025-12-02 07:28:38.615932536 +0000 UTC m=+334863.429710108: ✖️🔁 reset by wlwilliamx.
• 2025-12-02 07:47:27.525711271 +0000 UTC m=+335992.339488843: ☑️ agreed by hongyunyan.

[hongyunyan]

/hold