Add per-constraints feature for Sweep, with docs and tests

[AiKiAi-stack]

Summary

This PR adds support for per-strategy constraints in the sweep benchmarking mode, allowing constraint parameters to be c2onfigured individually for each strategy phase of the sweep.

Details

Core Implementation

• Added a per_constraints field in the SweepProfile class to store per-strategy constraints.
• Introduced a next_strategy_constraints method to dynamically compute and apply constraints based on the current strategy index.
• per_constraints is only allowed in sweep mode, and the constraint list must not contain None values.
• Added a --per-constraints CLI option that accepts constraints in JSON format.

Testing

• Add unit tests for test_per_constraints.
• Added tests for the CLI --per-constraints parameter in test_main.

Documents

• Create guide in benchmark.md how to use --per-constraints with --profile sweep via the CLI and within a JSON scenario configuration file.

Test Plan

Automated Testing

1. Run --per-constraints in CLI: pytest tests/test_main.py
2. Run pytest tests/unit/benchmark/

Manual Testing

1. Start the mock server:
   guidellm mock-server --port 8000
2. Test scenario file:
   { "target": "http://localhost:8000", "profile": "sweep", "rate": 5, "per_constraints": { "max_requests": [20, 100, 200, 200, 300], "max_errors": [1, 10, 10, 20, 30] }, "max_seconds": 60, "data": [ "prompt_tokens=512,output_tokens=256" ] }
   Expected: each strategy terminates at its respective max_requests as specified in the per-constraints.
3. Test CLI parameter
   guidellm benchmark --target http://localhost:8000 --profile sweep --rate 5 --per-constraints " {\"max_seconds\": [10,15,20,25,30]}" --max-requests 1000 --data "prompt_tokens=128,output_tokens=256"
   Expected: each strategy terminates at its respective max_seconds as specified in the per-constraints.

Related Issues

issue451:[Usage] Per-strategy max_requests constraints not respected in Sweep Mode

• Resolves #

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