Distributed Test Generation Using Logical Timestamp Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Generating distributed test programs for distributed systems with multiple execution engines poses challenges in ensuring synchronized access to shared resources, leading to non-deterministic states that hinder verification and debugging.
Innovation Solution
A test generation software employs a logical timestamp system to synchronize instructions across execution engines by maintaining up-to-date access histories, ensuring that only the most recent instructions are executed, and using SET and WAIT-AND-CLEAR instructions to manage event synchronization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If distributed test programs execute parallel instructions across multiple execution engines, then test coverage and productivity are improved, but synchronization of shared resources becomes difficult leading to non-deterministic states
Solution Approach 1:
The system performs preliminary actions by generating logical timestamps and access histories before executing parallel instructions. Each execution engine receives pre-synchronized timestamps that dictate the order of operations, ensuring deterministic state transitions even during parallel execution. This preliminary synchronization prevents race conditions and ensures reliable test results while maintaining high productivity.
2Ease of operation
If manual test crafting is used to mimic real-life operations, then ease of operation is improved, but test coverage is limited to a small fraction of system capabilities
Solution Approach 1:
The system creates simplified models or templates of real-life operations that can be automatically instantiated and varied. Instead of manually crafting each test case, the system generates multiple copies of test patterns with different parameters, covering a broader range of system capabilities while maintaining the operational realism of manual testing. This approach preserves ease of operation through template-based design while dramatically expanding test coverage.
3Adaptability or versatility
If automatic test generation is used to exercise full system capabilities, then test coverage is improved, but complexity of test synchronization increases
Solution Approach 1:
The system manages synchronization complexity by dynamically adjusting parameters such as logical timestamps, access histories, and event synchronization points. Rather than implementing a fixed complex synchronization protocol, the system adapts these parameters based on the specific test scenario and system state, enabling full capability coverage with manageable complexity through parameter-driven flexibility.
Data Source
AI summary
A method of generating instructions to be executed by a plurality of execution engines that shares a resource is provided. The method comprises, in a first generation step: reading a first engine logical timestamp vector of a first execution engine of the execution engines, the logical timestamp representing a history of access operations for the resource; determining whether the first engine logical timestamp vector includes a most-up-to-date logical timestamp of the resource in the first generation step; based on the first engine logical timestamp vector including the most-up-to-date logical timestamp of the resource in the first generation step, generating an access instruction to be executed by the first execution engine to access the resource; and scheduling the first execution engine to execute the access instruction.