[yuseok89]

The dashboard polls for running or queued Dag runs to decide whether to auto-refresh, every 3 seconds while runs are active. The check fetched one Dag run ordered by id. When the statistics from the last ANALYZE count some pending runs, Postgres serves that by scanning dag_run by primary key from the oldest run, and since pending runs are the newest it reads nearly the whole table. Only the count is used, so the check now asks for no rows and reads total_entries.

Measured on Postgres with 5M finished runs, through the real endpoint.

Running or queued runs	Before (limit=1)	After (limit=0)
70	3.3 to 11.8 s	1 ms

The new test serves the endpoint from an msw handler that returns only limit rows with the full count in total_entries, as the API does. It checks that refresh still turns on and that every request asks for limit=0, and it fails on main.

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  • Claude Code (Opus 5.5)

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[github-actions]

Backport successfully created: v3-4-test

Note: As of Merging PRs targeted for Airflow 3.X
the committer who merges the PR is responsible for backporting the PRs that are bug fixes (generally speaking) to the maintenance branches.

In matter of doubt please ask in #release-management Slack channel.

Status	Branch	Result
✅	v3-4-test