Hourly Schedules

Hourly cron schedules occupy a unique position in the spectrum of job scheduling: they're frequent enough to keep data fresh and systems responsive, but infrequent enough to run without significant operational overhead. Whether you're refreshing a cache, synchronising data from an external API, or running metrics aggregation, interval-based scheduling is one of the most common patterns in production systems.

Understanding Hourly Cron Syntax

• 0 * * * * — At minute 0 of every hour. Fires 24 times per day at the top of each hour.
• 30 * * * * — At minute 30 of every hour. Useful for offsetting from top-of-hour traffic.
• 0 */2 * * * — Every 2 hours. Fires at 00:00, 02:00, 04:00, etc.
• 0 */3 * * * — Every 3 hours. 8 times per day.
• 0 */4 * * * — Every 4 hours. 6 times per day.
• 0 */6 * * * — Every 6 hours. Fires at midnight, 6 AM, noon, and 6 PM.
• 0 9-17 * * 1-5 — Every hour from 9 AM to 5 PM, Monday through Friday.

Common Use Cases for Hourly Schedules

Cache Invalidation and Data Refresh

A cache refresh job at 0 * * * * ensures stale data is never more than 60 minutes old. For less volatile data, 0 */4 * * * or 0 */6 * * * reduces load while maintaining acceptable freshness.

External API Synchronisation

SaaS platforms routinely sync data from external sources. API rate limits often constrain frequency, making a scheduled poll at 0 */2 * * * for moderately volatile data the appropriate pattern.

Metrics Aggregation and Reporting

Running aggregation jobs at 5 * * * * (5 minutes past the hour) rather than 0 * * * * gives the previous hour's data a brief window to fully settle before aggregation begins.

Best Practices for Hourly Scheduled Jobs

• Offset from the top of the hour. Use 15 * * * * or 30 * * * * to avoid thundering herd at each hour boundary.
• Verify step semantics. 0 */3 * * * fires at 00:00, 03:00, 06:00—always starting from hour 0.
• Set execution time budgets. An hourly job should complete well within its interval.
• Implement idempotency for retries. If an hourly job fails and is retried, it should produce the same outcome.
• Consider drift. "Every hour" means at defined clock positions, not 60 minutes after the last run completed.