Artemis: Optimize model version validation lookup performance

[mike-turintech]

This pull request optimizes the performance of model version validation in the ModelVersionValidator class.

Previously, the validateModelVersion method used a stream and filter operation on a list of supported versions for a given ModelType. This approach had a time complexity of O(N), where N is the number of supported versions.

To improve performance, a new EnumMap<ModelType, Set<String>> called validVersionSets has been introduced. This map, populated during initialization, stores supported versions for each ModelType in a HashSet. This allows for efficient O(1) average time complexity lookups using Set.contains().

The method has been refactored to utilize this new, faster lookup mechanism. Additionally, HashMap instances keyed by ModelType were replaced with the more performant EnumMap.

Minor refactoring includes assigning lists to local variables and using Collections.emptyList().

These changes significantly improve the performance of version validation without altering external behavior.

Detailed Score Information

Score Details

This section contains detailed information about the performance scores for top 5 scored suggestions.

Top Performing Changes

1. src/main/java/com/llmproxy/service/llm/ModelVersionValidator.java:1-86 - Mean Improvement: 0.68, Mean Original Score: 4.50

• 🟢 Performance (Change: +1.90): The changes significantly improve performance. The original used a List and streamed through it on every validation, giving O(n) checks. The new code creates a HashSet per ModelType, enabling O(1) lookup in validateModelVersion. Furthermore, EnumMap replaces HashMap for enum keys, reducing memory/CPU footprint. These changes will provide measurable improvements especially for frequently called validation.

• 🟢 Quality (Score: 4.71; Change: +0.33): The changes slightly improve code quality and maintainability. Use of EnumMap better reflects intent for enum map keys. Extraction of lists and enhanced immutability improve clarity. Valid sets are clearly separated for lookup logic. However, the number of fields increases, and some may think the double map structure mildly increases complexity, but overall, code is clearer and better structured.

• 🟢 Value (Change: +1.83): The changes significantly improve performance and maintainability of the ModelVersionValidator. By replacing HashMap with EnumMap for enum-based keys, performance is improved. The addition of HashSet for O(1) lookups instead of stream filtering reduces time complexity for the validation operation. The code is also better structured with variables defined separately before being added to maps. Using Collections.emptyList() instead of List.of() for the default case is also a minor optimization. These changes would be particularly valuable in high-traffic scenarios where the validator is called frequently.