Snowflake warehouses that never auto-suspend or wait longer than 120 seconds

Idle seconds bill at the full warehouse rate

A Snowflake warehouse consumes credits for every second it runs, with a 60-second minimum each time it starts. Auto-suspend is what stops it after the last query. CREATE WAREHOUSE sets AUTO_SUSPEND to 600 seconds by default, and a value of 0 or NULL means the warehouse never suspends, which Snowflake warns can consume significant credits, especially on larger sizes.

Snowflake’s own warehouse guidance recommends a low value such as 5 or 10 minutes or less because billing is per second. On a Medium warehouse, at 4 credits an hour on Gen1, every ten-minute tail after a burst of queries is two-thirds of a credit spent on nothing.

Reading the setting from SHOW WAREHOUSES

SHOW WAREHOUSES
  ->> SELECT "name", "size", "auto_suspend", "auto_resume"
      FROM $1
      WHERE "auto_suspend" IS NULL
         OR "auto_suspend" = 0
         OR "auto_suspend" > 120
      ORDER BY "size";

The ->> pipe operator lets you filter SHOW WAREHOUSES output; column names are lowercase and must be double-quoted. A null auto_suspend means the warehouse will not suspend on its own. SHOW WAREHOUSES lists only warehouses your role has some privilege on, so run it with a role that can see all of them.

Three settings that trigger the finding

ZopNight reads the warehouse’s auto-suspend value and fires when it is missing, empty, zero, or a number above 120 seconds. Because the Snowflake default is 600 seconds, any warehouse created without an explicit value qualifies. No usage metric is involved: a warehouse is flagged for its configuration even if it has not run recently.

Values the check accepts

Any auto-suspend of 120 seconds or less passes. The rule does not look at how often queries arrive, so it will not tell you that 60 seconds is too short for a workload with regular two-minute gaps. Warehouses that burn credits with no queries at all are covered separately by Snowflake Warehouse Idle.

No dollar figure, and what the idle tail costs

This is a governance finding with no saving attached, since the idle time between queries depends on traffic patterns ZopNight does not model here. The waste per suspend cycle is the gap between the last query and the suspend timer, at the warehouse’s hourly credit rate.

Tightening auto-suspend

1. Look at the warehouse’s typical gap between queries. If gaps are shorter than the new timer, the warehouse will keep running anyway; if they are just longer, each resume costs the 60-second minimum.
2. Set a short timer: ALTER WAREHOUSE <name> SET AUTO_SUSPEND = 60; Snowflake checks for suspension about every 30 seconds, so values below 30 or not a multiple of 30 may not behave as expected.
3. Keep AUTO_RESUME = TRUE so the next query wakes it.