# Feedback for Iteration 2a469a33

## Decision: FIX

## Status
- **QA**: ❌ Tests failed (2 of 56 benchmarks exceed CV threshold)
- **Code Review**: ✅ Approved (configuration correct)
- **Progress**: 96.4% benchmarks passing (54/56)

## Critical Issue
Two benchmarks still exceed the CV < 10% threshold despite correct configuration:

### 1. `warm_execution_with_print` - CV = 48.13% (CRITICAL)
**File**: `benches/execution_benchmarks.rs`
**Root cause**: Print statements writing to SmallString buffer causing extreme variance

**Required fix**:
```rust
// In benches/execution_benchmarks.rs, update the benchmark group for warm_execution_with_print:
group.sample_size(2000)  // Increase from 1000
    .measurement_time(std::time::Duration::from_secs(20));  // Increase from 10s
```

This specific benchmark needs higher sample size and measurement time due to I/O buffer variance.

### 2. `function_with_all_operators` - CV = 10.99% (BORDERLINE)
**File**: `benches/function_call_overhead.rs`
**Root cause**: Only 0.99% over threshold - needs slightly more measurement time

**Required fix**:
```rust
// In benches/function_call_overhead.rs, update the benchmark group for function_with_all_operators:
group.sample_size(1000)
    .measurement_time(std::time::Duration::from_secs(15));  // Increase from 10s to 15s
```

## Specific Actions Required

1. **Edit benches/execution_benchmarks.rs**:
   - Locate the benchmark group configuration for `warm_execution_with_print`
   - Change to: `.sample_size(2000).measurement_time(std::time::Duration::from_secs(20))`

2. **Edit benches/function_call_overhead.rs**:
   - Locate the benchmark group configuration for `function_with_all_operators`
   - Change to: `.measurement_time(std::time::Duration::from_secs(15))`
   - Keep `.sample_size(1000)` unchanged

3. **Keep all other 54 benchmarks unchanged** (they pass with current config)

4. **Verify the fix**:
   ```bash
   cargo bench --bench execution_benchmarks
   cargo bench --bench function_call_overhead
   ```

## Current Status
- ✅ **AC4.2**: All 664 tests pass (377/377 unit tests verified)
- ❌ **AC4.4**: 54/56 benchmarks pass CV < 10% (need 56/56)
- ❌ **M5**: Statistical stability not achieved for all benchmarks

## Why This Iteration Failed
The standard configuration (1000 samples, 10s measurement) works for 96.4% of benchmarks but two edge cases need higher thresholds:
- I/O operations (print) require 2x samples and 2x time
- Complex operators require 1.5x measurement time

## Not a Stuck Loop
This is **NOT** a stuck pattern because:
- Each iteration has made measurable progress
- We now have specific benchmark names and precise CV values
- The fix is targeted to only 2 files
- Previous iterations addressed different issues (wrong config, batching loops)

---

**Action**: Apply the two targeted configuration changes above. Do NOT change any other benchmark files.
