Major System Overhaul

[virjilakrum]

Real-time Dashboard, Enhanced Error Handling & Structural Refactoring

1. Real-time Dashboard Engine Overhaul

What Changed:

• Implemented async-aware mutex locking with tokio::sync::Mutex replacing std::sync::Mutex
• Added 500ms auto-refresh loop using tokio::select! for concurrent UI updates and input handling
• Rewrote terminal drawing logic with ratatui's List widgets for dynamic GPU/user list rendering
• Integrated non-blocking input handling with crossterm::event::poll

// New event loop structure
loop {
    let timeout = tokio::time::sleep(Duration::from_millis(500));
    tokio::select! {
        _ = timeout => {
            // Async lock acquisition
            let gpupool = gpupool.lock().await;
            let users = users.lock().await;
            terminal.draw(|f| { /* ... */ })?;
        }
        event = crossterm::event::read() => {
            // Input handling
        }
    }
}

---

2. Enhanced Error Handling System

Key Improvements:

• Added detailed error context propagation using anyhow::Context
• Implemented automatic user creation with 1M default credits for demo purposes
• Created custom error types for critical operations:

#[derive(Debug, thiserror::Error)]
pub enum AllocationError {
    #[error("GPU {0} not found")]
    GpuNotFound(u32),
    #[error("Insufficient credits: needed {needed:.2}, available {available:.2}")]
    InsufficientCredits { needed: f64, available: f64 },
}

• Added backpressure control in API middleware using governor rate limiting

---

3. GPU Management Core Refactoring

Structural Changes:

• Removed legacy pricing map in favor of algorithmic cost calculation:

fn calculate_cost(&self, gpu_id: u32) -> f64 {
    let gpu = self.gpus.get(&gpu_id).unwrap();
    gpu.vram_mb as f64 * 0.1 + gpu.compute_units as f64 * 2.0
}

• Standardized GPU initialization with realistic hardware profiles:

GPUPool {
    gpus: HashMap::from([
        (0, VirtualGPU::new(8192, 32)),  // Mid-range GPU
        (1, VirtualGPU::new(16384, 64)), // High-end GPU
    ])
}

• Added atomic reference counting for GPU state sharing

---

4. User Management System Upgrade

New Features:

• Auto-creation of users with default 1M credit balance
• Credit deduction validation with detailed error reporting
• Added user activity tracking:

pub struct User {
    pub last_active: DateTime<Utc>,
    pub session_count: u32,
    pub total_spent: f64,
}

---

5. Testing & Validation Suite

Added Test Cases:

#[tokio::test]
async fn test_concurrent_allocations() {
    // Stress test with 100 concurrent requests
}

Example Test Commands:

# Test real-time dashboard updates
cargo run --release --bin dashboard &

# Generate load
for i in {1..10}; do
    cargo run --release -- rent --gpu-id 0 --user "user$i" --duration 10
done

---

6. Dependency & Configuration Updates

• Upgraded tokio to 1.36 with full features
• Added ratatui 0.26 and crossterm 0.27 for terminal UI
• Configured default-run in Cargo.toml for better CLI handling
• Removed legacy NVML/Windows API code paths

---

7. CI/CD Improvements

• Added release profile optimization flags:

[profile.release]
lto = true
codegen-units = 1

• Configured automated rustfmt/clippy checks
• Added basic healthcheck endpoint to API

---

Migration Notes:

1. Existing users will be automatically migrated with 1M credit balance
2. GPU pricing model changed from fixed to dynamic calculation
3. Dashboard now requires tokio runtime for async operation

Known Issues:

• Dashboard may show brief inconsistencies during high contention
• GPU release notifications have 500ms propagation delay

Future Roadmap:

• Implement JWT-based authentication layer
• Add GPU utilization graphs using plotters crate
• Develop WebSocket API for browser-based dashboard