ATF Test Generator and Cloud Runner Lane Allocation Guidance

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This article is meant for Automated Test Framework users who use Test Generator and Cloud Runner and want to increase the speed and accuracy of their test authoring and execution. It explains the key information needed for additional lane allocation in Test Generator and Cloud Runner.

Test Generator and Cloud Runner give Automated Test Framework the ability to intelligently author and generate tests while executing them on ServiceNow Cloud infrastructure.

A critical aspect is the allocation of lanes or threads on ATF Test Generator and Cloud Runner. The allocation limit is 12 lanes per instance. There are important nuances to consider for an optimal distribution strategy, especially around node allocation.

Lane Allocation Breakdown

1. Allocation Limits: The limit of 12 lanes per instance sets the upper boundary for allocation.
2. Practical Allocation Scenarios: For example, a customer purchasing 2 packs receives 12 lanes in total, including the 2 default lanes. This reaches the per instance limit and requires at least 2 nodes for efficient utilization.
3. Node Per Pack Allocation: The allocation model by pack is:
   • 1 pack: 7 lanes total, ideally using 1 node, although 2 nodes are typically provisioned for redundancy and load balancing.
   • 2 packs: 12 lanes total, distributed across 2 nodes.
   • The 12 lane per instance maximum applies regardless of node count. Provisioning additional nodes beyond the recommended 2 improves redundancy and distribution, but it does not raise the total lane ceiling above 12.
4. Optimization Strategies: To ensure efficient resource utilization, consider these strategies:
   • Mutually Exclusive Tests: Use techniques to isolate mutually exclusive tests. Enable sequential execution or smaller group executions to maximize parallelism for tests that do not conflict. In other words, avoid running tests that share the same records.
   • Off Peak Scheduling: Schedule Cloud Runner tests to run during windows when other scheduled jobs are not executing. Concurrent scheduled jobs compete for the same instance resources, so separating test runs from other batch activity reduces contention and protects overall instance performance.

Default number of lanes upon installation of Test Generator and Cloud Runner	2 lanes
Number of lanes for a pack	5 lanes