loki5512344
91835402b3
- Core world model (World, Dimension, Tile, Terrain, Platform) - NBT reader/writer with full tag support - Anvil region (.mca) format reader with chunk parsing - Block palette compression and export - Biome database with Minecraft 1.21 biomes - CLI commands: new, import, export, info, render - GUI application with egui (viewport, tools, undo/redo) - Noise-based heightmap generation and editing operations License: GPL-3.0-or-later
45 lines
1.7 KiB
Markdown
Executable file
45 lines
1.7 KiB
Markdown
Executable file
# Hot-spot Analysis
|
||
|
||
> Updated: 2026-05-27
|
||
|
||
## Results
|
||
|
||
After baseline measurement, **only 1 benchmark exceeded 10ms**:
|
||
|
||
| Benchmark | Baseline | Optimized | Improvement |
|
||
|-----------|----------|-----------|-------------|
|
||
| `world/new_default` | **10.2 ms** | **1.53 ms** | **85%** |
|
||
|
||
All other benchmarks are well within the threshold (<7ms).
|
||
|
||
## Optimisation Applied
|
||
|
||
### `World::new()` — parallel tile generation
|
||
|
||
**Problem**: `World::new()` generated 9 noise heightmaps sequentially in nested `for` loops
|
||
(`-1..=1 × -1..=1`). Each tile calls `NoiseHeightMap::generate()` which does 16384 noise
|
||
samples × noise function calls. Total: 9 × 16384 = 147,456 noise evaluations.
|
||
|
||
**Fix**: Replaced sequential loop with `rayon::par_iter()` over the tile coordinates.
|
||
Noise heightmap generation per tile is embarrassingly parallel — tiles are fully independent.
|
||
|
||
**Result**: 10.2ms → 1.53ms (6.7x speedup on 8-core machine).
|
||
|
||
## Other Candidates (no action needed)
|
||
|
||
### NBT parsing (max 52 µs)
|
||
No action needed — already below 100µs. Zero-copy optimisations would add complexity
|
||
with negligible benefit.
|
||
|
||
### Render (max 3.1 ms)
|
||
No action needed — pixel-by-pixel rendering at 3ms for 384×384 is acceptable for a
|
||
preview renderer. If tile count grows to 100+, chunk-level parallelism via rayon
|
||
would help. Not needed now.
|
||
|
||
### JSON serialization (max 5.3 ms / 6.4 ms)
|
||
Bottleneck is serde serializing 9 tiles × 16384-element arrays. Potential future optimisations:
|
||
- Streaming serialization with `serde_json::to_writer`
|
||
- Custom serializer using binary formats
|
||
- Compressed tile data representation
|
||
|
||
Not needed now — user-facing operations (`new`, `paint`, `height` edits) are sub-millisecond.
|