# MVGAL Implementation Strategy and Gap Analysis

## 1. Vendor Driver Gap Analysis

To achieve full MVGAL integration, several gaps in existing vendor drivers must be addressed or worked around:

### NVIDIA
- **Gap:** Proprietary userspace limits deep command-buffer interception.
- **Strategy:** Rely on the `open-gpu-kernel-modules` for kernel-side coordination and use a sophisticated LD_PRELOAD/Layer for userspace API interception. Use NV-P2P for high-speed transfers.

### AMD
- **Gap:** PAL (Platform Abstraction Library) is complex and specific to AMD.
- **Strategy:** Target the Vulkan level for AMDVLK and use the standard DRM/AMDGPU ioctls for memory and sync. Leverage TTM for memory management insights.

### Intel
- **Gap:** Different driver stacks for integrated (i915) and discrete (xe) GPUs.
- **Strategy:** Implement a dual-backend for Intel that detects which kernel driver is in use and adapts its ioctl patterns.

### Moore Threads
- **Gap:** Unmaintained out-of-tree driver.
- **Strategy:** Provide a "best-effort" wrapper. Contribute minimal fixes to `mtgpu-drv` to support modern DMA-BUF and fence interfaces if needed.

## 2. Missing Core Components (MVGAL-Specific)

1. **Unified Virtual Memory (UVM) Engine:**
   - Need a kernel-side component to manage a shared address space across GPUs with different MMU capabilities.
   - Proposed implementation: `mvgal_uvm.c` in the kernel, using `hmm_range_fault` for page migration.

2. **Transparent Command Stream Splitter:**
   - Need a userspace component that can take a single Vulkan command buffer and split it into N buffers for N GPUs.
   - This is the most complex component and will be implemented in `src/userspace/execution/workload_splitter.c`.

3. **Power-Aware Load Balancer:**
   - A scheduler that considers the power-per-watt efficiency of each GPU when distributing tasks.
   - Implementation: Extend `runtime/daemon/scheduler.cpp` with efficiency curves.

## 3. Technology Stack Rationale

- **C/C++:** Industry standard for drivers and performance-critical userspace.
- **Rust:** Used for "Safety Shims" where complex logic meets raw pointers.
- **CMake:** Best-in-class support for multi-language projects (C/C++/Rust/Go).
- **Go:** Ideal for the REST API and monitoring dashboard backend due to excellent concurrency and networking.
- **Qt 6:** Provides a modern, high-performance GUI for system management.

## 4. Initial Implementation Plan (Next 3 Months)

### Month 1: Kernel & HAL Refinement
- Stabilize the `mvgal_vendor_ops` interface.
- Implement basic DMA-BUF P2P sharing between NVIDIA and AMD.
- Prototype the UVM page migration handler.

### Month 2: Userspace & Interception
- Complete the Vulkan Layer's `VkDevice` virtualization.
- Implement the "Strategy" pattern in the scheduler (AFR, SFR, Hybrid).
- Integrate Rust safety shims into the daemon.

### Month 3: Compatibility & Testing
- Proton/Wine integration for D3D11/D3D12 games.
- Benchmarking and optimization of synchronization overhead.
- Release "Alpha" version for developer testing.
