> ## Documentation Index
> Fetch the complete documentation index at: https://checklyhq.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Scheduling

> Learn about scheduling strategies in Checkly

## Scheduling Strategies

Checkly provides two scheduling strategies for running checks: **Round-robin** or **Parallel scheduling**. To select a scheduling strategy go to ‘Scheduling and locations’ when creating or editing a check.

### Round-robin

Using **Round-robin Scheduling**, your check will run on one of the selected locations each time it is scheduled. The next check run will be scheduled on a different location from the list until all locations have been run once, and the check rotates back to the first location in the list.

When using the **Round-robin Scheduling** strategy you can choose to have retries to run from a random location of the ones selected, or run it from the same location as the first attempt.

Use **Round-robin Scheduling** when the service you are monitoring can be considered available as long as at least one location is available and detecting a regional outage is not critical.

### Parallel

With **Parallel Scheduling**, each time the check is scheduled it will run once from each selected location. When running a check in parallel, retries will always be run from the same location as the first attempt.

Use **Parallel Scheduling** to reduce detection times for regional outages and reduce time to detect service degradations that impact the customer experience.

## Best Practices

### Frequency Guidelines by Service Criticality

**Critical Production Services:**

* **Frequency**: Every 10 Seconds - 2 Minutes
* **Examples**: Payment processing, user authentication, core APIs
* **Rationale**: Immediate detection of issues affecting users

**Important Services:**

* **Frequency**: Every 5-10 minutes
* **Examples**: Secondary APIs, admin interfaces, reporting tools
* **Rationale**: Quick detection with reasonable resource usage

**Non-Critical Services:**

* **Frequency**: Every 15-30 minutes
* **Examples**: Documentation sites, internal tools, dev environments
* **Rationale**: Monitor availability without excessive overhead

### Frequency Guidelines by Service Type

**E-commerce Sites:**

* **Homepage**: Every 1 minute (critical for revenue)
* **Product Pages**: Every 5 minutes
* **Search API**: Every 2 minutes
* **Checkout Flow**: Every 30 seconds

**SaaS Applications:**

* **Login Endpoint**: Every 1 minute
* **Core Features**: Every 5 minutes
* **Admin Interfaces**: Every 15 minutes
* **Status Pages**: Every 10 minutes

**Database Servers:**

* **Primary Database**: Every 2 minutes
* **Read Replicas**: Every 5 minutes
* **Backup Systems**: Every 15 minutes

### Resource Impact Considerations

**Server Load Management:**

* Higher frequency = more requests to your servers
* Use round-robin scheduling to distribute load
* Consider rate limiting and caching implications
* Monitor your server metrics during frequency changes

**Monitoring Budget:**

* More frequent checks = higher monitoring costs
* Balance detection speed with budget constraints
* Review and adjust frequencies based on actual value

### Initial Configuration

1. **Start conservative** with 5-10 minute intervals
2. **Monitor high-impact services more frequently**
3. **Adjust based on actual failure patterns**
4. **Consider business hours and user activity**

### Ongoing Optimization

* **Review frequency effectiveness** quarterly
* **Adjust during high-risk periods** (deployments, traffic spikes)
* **Balance detection speed with cost constraints**
* **Use data-driven decisions** based on incident history

### Documentation and Communication

* **Document scheduling rationale** for different services
* **Communicate frequency changes** to relevant teams
* **Track scheduling effectiveness** over time
* **Regular review with stakeholders**