# Unreal Engine 5.4.1 Disk Space Optimization Guide

## Overview

This guide explains how the installation script reduces disk space requirements from ~100GB+ to approximately **~300GB** (1/3 of 926GB available).

## Optimization Strategies

### 1. Shallow Git Clone
- **Method**: Using `--depth=1` flag
- **Savings**: Reduces repository size from ~15GB to ~10GB
- **Trade-off**: Cannot access full git history (not needed for building)

### 2. Build Only Development Editor
- **Method**: Building only `UnrealEditor` target (Development configuration)
- **Savings**: ~50-70GB (skips Shipping builds, all platform builds, templates)
- **Command**: `make -j4 UnrealEditor`
- **Trade-off**: Cannot package Shipping builds without rebuilding

### 3. Limited CPU Cores
- **Method**: Using 4 cores instead of all available cores
- **Benefit**: Reduces memory usage, prevents system overload
- **Build Time**: 4-6+ hours (vs 2-4 hours with all cores)
- **Command**: `make -j4 UnrealEditor`

### 4. Cleanup Intermediate Files
- **Method**: Removing `.o`, `.obj`, `.d`, `.pch` files after build
- **Savings**: ~20-30GB
- **Location**: `Engine/Intermediate/`

### 5. Skip Optional Components
- **Not Built**:
  - Shipping builds
  - All platform builds (only Linux)
  - Project templates
  - Sample projects
  - Documentation builds
  - Additional tools (only Editor)

## Disk Space Breakdown

### Typical Installation Sizes

| Component | Full Build | Optimized Build |
|-----------|------------|-----------------|
| Source code | ~10GB | ~10GB |
| Dependencies | ~20GB | ~20GB |
| Development Editor | ~40GB | ~40GB |
| Shipping builds | ~30GB | **0GB** (skipped) |
| Templates/Samples | ~15GB | **0GB** (skipped) |
| Intermediate files | ~30GB | ~10GB (cleaned) |
| **Total** | **~145GB** | **~80GB** |

### Additional Space Considerations

- **Project files**: ~5-10GB per project
- **Cooked content**: ~10-20GB per project
- **Derived data cache**: ~5-10GB
- **Total with project**: ~100-110GB

## Configuration Options

### Change CPU Cores

Edit `scripts/install_ue5_5.4.1.sh`:

```bash
# Find this line (around line 170):
NUM_CORES=4

# Change to desired number:
NUM_CORES=8  # Use 8 cores
NUM_CORES=2  # Use 2 cores (slower but less memory)
```

### Build Additional Targets

If you need Shipping builds later:

```bash
cd ~/UnrealEngine
make -j4 UnrealEditor-Linux-Shipping
```

### Build Templates (Optional)

If you need project templates:

```bash
cd ~/UnrealEngine
make -j4 UnrealEditor UnrealGame
```

## Further Disk Space Reduction

### 1. Remove Source After Build (Advanced)

**Warning**: This prevents rebuilding from source. Only do this if you're certain you won't need to rebuild.

```bash
# After successful build, remove source files
cd ~/UnrealEngine
rm -rf Engine/Source/Editor
rm -rf Engine/Source/Developer
# Keep Engine/Source/Runtime for runtime features
```

**Savings**: ~5-10GB
**Risk**: Cannot rebuild without re-cloning

### 2. Use Symbolic Links for Projects

Store projects on a different drive and use symbolic links:

```bash
# Create project on larger drive
mkdir /mnt/d/Projects/DubaiMetaverse
ln -s /mnt/d/Projects/DubaiMetaverse ~/Projects/DubaiMetaverse
```

### 3. Clean Derived Data Cache Periodically

```bash
# Remove Unreal Engine derived data cache
rm -rf ~/.config/Epic/UnrealEngine/5.4/DerivedDataCache
```

**Savings**: ~5-10GB
**Trade-off**: Assets will need to be recompiled on next launch

### 4. Compress Installation Directory

```bash
# Create compressed archive (optional, for backup)
cd ~
tar -czf UnrealEngine-5.4.1-backup.tar.gz UnrealEngine/
```

## Monitoring Disk Usage

### Check Installation Size

```bash
du -sh ~/UnrealEngine
```

### Check Disk Space

```bash
df -h ~
```

### Find Large Files

```bash
cd ~/UnrealEngine
find . -type f -size +100M -exec ls -lh {} \; | sort -k5 -hr | head -20
```

## Recommended Settings

### For Development (Current Setup)
- **CPU Cores**: 4
- **Build Target**: Development Editor only
- **Disk Space**: ~80-100GB
- **Build Time**: 4-6 hours

### For Full Build (If Space Available)
- **CPU Cores**: 8-16
- **Build Target**: Development + Shipping
- **Disk Space**: ~150GB+
- **Build Time**: 2-4 hours

## Troubleshooting

### Out of Disk Space During Build

1. **Clean intermediate files**:
   ```bash
   cd ~/UnrealEngine
   find Engine/Intermediate -type f -name "*.o" -delete
   ```

2. **Reduce parallel jobs**:
   ```bash
   # Edit script: change NUM_CORES=4 to NUM_CORES=2
   ```

3. **Build incrementally**:
   ```bash
   # Build one module at a time (slower but uses less space)
   make -j1 UnrealEditor
   ```

### Build Fails Due to Memory

- Reduce CPU cores: `NUM_CORES=2`
- Close other applications
- Add swap space if needed

## Summary

The optimized installation uses:
- ✅ **~80-100GB** disk space (vs ~150GB+ full build)
- ✅ **4 CPU cores** (configurable)
- ✅ **Development Editor only** (sufficient for development)
- ✅ **Automatic cleanup** of intermediate files

This provides approximately **1/3 of 926GB** usage while maintaining full development capabilities.

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**Version**: 1.0
**Last Updated**: 2024