Snowflake warehouses that burned credits for 14 days with zero queries

A resumed warehouse bills whether or not queries arrive

Snowflake meters a virtual warehouse for the time it is running, not for the queries it serves. Warehouse billing is per second with a 60-second minimum each time the warehouse starts, and credit burn doubles with each size step, from 1 credit an hour for an X-Small Gen1 warehouse upward. An X-Small left running around the clock therefore uses 24 credits a day, or 336 across two weeks, and a Medium four times that.

Auto-suspend normally stops this. It is on by default, but setting AUTO_SUSPEND to 0 or NULL means the warehouse never suspends, which Snowflake itself warns can consume significant credits. A warehouse held open that way, or resumed repeatedly by a tool that then sends nothing, is the case this rule catches.

Checking metering against query history yourself

Two ACCOUNT_USAGE views answer the question. This query returns warehouses with compute credits in the last 14 days and no queries attributed to them:

WITH burn AS (
  SELECT warehouse_name, SUM(credits_used_compute) AS compute_credits
  FROM SNOWFLAKE.ACCOUNT_USAGE.WAREHOUSE_METERING_HISTORY
  WHERE start_time >= DATEADD('day', -14, CURRENT_TIMESTAMP())
  GROUP BY warehouse_name
  HAVING SUM(credits_used_compute) > 0
), work AS (
  SELECT warehouse_name, COUNT(*) AS queries
  FROM SNOWFLAKE.ACCOUNT_USAGE.QUERY_HISTORY
  WHERE start_time >= DATEADD('day', -14, CURRENT_TIMESTAMP())
    AND warehouse_name IS NOT NULL
  GROUP BY warehouse_name
)
SELECT b.warehouse_name, b.compute_credits
FROM burn b
LEFT JOIN work w ON w.warehouse_name = b.warehouse_name
WHERE COALESCE(w.queries, 0) = 0
ORDER BY b.compute_credits DESC;

WAREHOUSE_METERING_HISTORY can lag by up to 3 hours and QUERY_HISTORY by up to 45 minutes, so the most recent hours are always incomplete. A role needs the USAGE_VIEWER and GOVERNANCE_VIEWER SNOWFLAKE database roles, or imported privileges on the SNOWFLAKE database, to read them. Then run SHOW WAREHOUSES LIKE '<name>'; and look at the auto_suspend column for each result.

Credits above zero and queries at zero across 14 days

The rule reads two hourly series for the warehouse: credits consumed and query count. Summed over the trailing 14 days, credits must be greater than zero and queries must be exactly zero. A single query anywhere in the window clears the warehouse. There is no size, edition or tag condition.

Warehouses that are not flagged as idle

If either series is missing or has no datapoints in the window, the rule does not fire: a Snowflake finding is never raised on absent evidence. A warehouse that ran real queries, even a handful, is left to the utilisation rules such as Snowflake Warehouse Under-Utilized. Loose auto-suspend on its own, with no wasted credits yet, is covered by Snowflake Warehouse Auto-Suspend Not Tuned.

The saving is the warehouse’s whole monthly bill

Suspending an idle warehouse stops all of its compute, so the saving equals the warehouse’s monthly cost as ZopNight prices Snowflake: credits multiplied by the credit rate for the account’s edition.

saving = monthly warehouse cost (credits x edition credit rate)
cost after suspend = 0 until the next real query resumes it

When no price is available for the warehouse, the saving would be zero and the finding is dropped instead of being shown as a $0 recommendation.

Suspending the warehouse and stopping a repeat

1. Suspend it: ALTER WAREHOUSE idle_wh SUSPEND; Running statements finish first, then the compute is released. The role needs OPERATE or MODIFY on the warehouse.
2. Leave AUTO_RESUME at its default of TRUE so a genuine query wakes the warehouse, paying only the 60-second minimum.
3. Put a limit on idle time: ALTER WAREHOUSE idle_wh SET AUTO_SUSPEND = 60;
4. Find whatever resumed it (a BI connection, an orchestrator step, a manual RESUME) and fix or remove it.