foxhunt/docs/archive/historical/LOAD_TEST_SPLIT_SUMMARY.md

Load Test Split Summary

Problem

Single tests/load_test_trading_service.rs file was taking too long to compile, causing development friction.

Solution

Split the monolithic test file into 5 smaller, focused test modules with shared common infrastructure.

Files Created

1. Common Infrastructure

File: /home/jgrusewski/Work/foxhunt/tests/load_tests/src/lib.rs

• Shared PerformanceMetrics struct for aggregating test results
• Common create_order_request() function for generating test orders
• Shared connect_trading_service() function for gRPC connections
• Proto-generated gRPC client code

2. Baseline Tests

File: /home/jgrusewski/Work/foxhunt/tests/load_tests/tests/load_test_baseline.rs

• Single-client latency baseline measurement
• 1,000 sequential orders
• Compile time: 20 seconds ✅

3. Concurrent Tests

File: /home/jgrusewski/Work/foxhunt/tests/load_tests/tests/load_test_concurrent.rs

• 100 concurrent client connections
• 100 orders per client (10,000 total)
• Compile time: 17 seconds ✅

4. Sustained Load Tests

File: /home/jgrusewski/Work/foxhunt/tests/load_tests/tests/load_test_sustained.rs

• Long-running 5-minute stress test
• 50 clients with rate limiting (10K orders/sec target)
• Marked with #[ignore] for explicit execution
• Compile time: 17 seconds ✅

5. Database & Resource Tests

File: /home/jgrusewski/Work/foxhunt/tests/load_tests/tests/load_test_database.rs

• Database write performance testing (5,000 orders)
• HTTP health check validation
• Prometheus metrics endpoint validation
• Compile time: 59 seconds ✅

6. Production Readiness Tests

File: /home/jgrusewski/Work/foxhunt/tests/load_tests/tests/load_test_production.rs

• Comprehensive production readiness assessment
• 50 clients × 200 orders (10,000 total)
• Success rate, throughput, and latency validation
• Compile time: 17 seconds ✅

Configuration Changes

Updated Files

1. tests/load_tests/Cargo.toml

   • Added 5 new [[test]] entries
   • Made reqwest non-optional (needed for health checks)
   • Removed obsolete health-checks feature

2. Cargo.toml (workspace root)

   • Added "tests/load_tests" to workspace members

3. tests/load_tests/build.rs

   • Fixed proto compilation to use new tonic-prost-build API

Compilation Performance

Test Module	Compile Time	Status
load_test_baseline	20.1s	✅ PASS
load_test_concurrent	17.5s	✅ PASS
load_test_sustained	17.6s	✅ PASS
load_test_database	59.0s	✅ PASS
load_test_production	17.6s	✅ PASS

All modules compile in under 2 minutes ✅

Running Tests

Individual Test Modules

# Baseline latency test
cargo test --manifest-path tests/load_tests/Cargo.toml --test load_test_baseline --release

# Concurrent connections test
cargo test --manifest-path tests/load_tests/Cargo.toml --test load_test_concurrent --release

# Sustained load test (long-running, marked #[ignore])
cargo test --manifest-path tests/load_tests/Cargo.toml --test load_test_sustained --release -- --ignored

# Database performance test
cargo test --manifest-path tests/load_tests/Cargo.toml --test load_test_database --release

# Production readiness test
cargo test --manifest-path tests/load_tests/Cargo.toml --test load_test_production --release

All Tests

# Run all load tests (excluding ignored)
cargo test --manifest-path tests/load_tests/Cargo.toml --release

# Run all including long-running tests
cargo test --manifest-path tests/load_tests/Cargo.toml --release -- --ignored --include-ignored

Key Improvements

1. Faster Compilation: Each module compiles independently in 17-59 seconds (vs. previous >2 minutes for monolithic file)
2. Better Organization: Tests grouped by logical functionality
3. Selective Execution: Run only relevant tests during development
4. Shared Infrastructure: Common code in lib.rs eliminates duplication
5. Incremental Builds: Changing one test doesn't recompile all tests

Technical Fixes Applied

1. Proto Structure Alignment: Updated SubmitOrderRequest to match actual proto definition

   • Removed: order_id, time_in_force fields
   • Added: account_id, metadata fields
   • Fixed: quantity and price types (string → double)

2. AtomicU64 Clone Issue: Removed Clone derive from PerformanceMetrics (AtomicU64 doesn't implement Clone)

3. Crate Name: Updated imports to use correct crate name integration_load_tests

4. Build Script: Fixed tonic_prost_build::compile_protos() API usage (single argument, not array)

Original File Status

The original /home/jgrusewski/Work/foxhunt/tests/load_test_trading_service.rs remains in place but has compilation errors due to outdated proto structure. It can be:

• Removed (tests are now in split modules)
• Updated with same fixes as split modules
• Kept as reference

Next Steps

1. ✅ All 5 split test modules compile successfully
2. ✅ Compilation times under 2-minute target
3. 📝 Consider removing or updating original load_test_trading_service.rs
4. 📝 Run tests to validate functionality
5. 📝 Update CI/CD pipeline to use new test structure

File Statistics

• Files created: 6 (1 lib + 5 test modules)
• Files modified: 3 (2 Cargo.toml + 1 build.rs)
• Total lines: ~1,200 lines across all files
• Common code: ~170 lines (shared infrastructure)
• Test code: ~1,030 lines (distributed across 5 modules)

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Date: 2025-10-11
Task: Split large load test file into smaller modules
Result: ✅ SUCCESS - All modules compile in <2 minutes