⚡️ Speed up function build_default_pretrains by 99%
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The optimization replaces an inefficient explicit loop with Python's built-in `dict.update()` method.
**Key change:** The original code iterates through `specific_default_pretrains.keys()` and assigns each key-value pair individually:
```python
for lang in specific_default_pretrains.keys():
default_pretrains[lang] = specific_default_pretrains[lang]
```
The optimized version uses a single `dict.update()` call:
```python
default_pretrains.update(specific_default_pretrains)
```
**Why this is faster:**
- `dict.update()` is implemented in C and performs bulk updates efficiently, avoiding Python's per-iteration overhead
- Eliminates 2,635 individual dictionary assignments (83.7% of total execution time in the original)
- Reduces from ~2,666 loop iterations with hash lookups to a single optimized C operation
**Performance gains are most significant when:**
- `specific_default_pretrains` contains many entries (like the 85+ language mappings in the test data)
- The function is called frequently, as the 98% speedup (232μs → 117μs) compounds across multiple calls
- Large-scale scenarios where dictionary operations dominate runtime, as evidenced by the test cases with hundreds of language mappings
The optimization maintains identical behavior while leveraging Python's optimized built-in methods for dictionary operations.
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📄 99% (0.99x) speedup for
build_default_pretrainsinstanza/resources/default_packages.py⏱️ Runtime :
232 microseconds→117 microseconds(best of227runs)📝 Explanation and details
The optimization replaces an inefficient explicit loop with Python's built-in
dict.update()method.Key change: The original code iterates through
specific_default_pretrains.keys()and assigns each key-value pair individually:The optimized version uses a single
dict.update()call:Why this is faster:
dict.update()is implemented in C and performs bulk updates efficiently, avoiding Python's per-iteration overheadPerformance gains are most significant when:
specific_default_pretrainscontains many entries (like the 85+ language mappings in the test data)The optimization maintains identical behavior while leveraging Python's optimized built-in methods for dictionary operations.
✅ Correctness verification report:
🌀 Generated Regression Tests and Runtime
⏪ Replay Tests and Runtime
To edit these changes
git checkout codeflash/optimize-build_default_pretrains-mh4h84ooand push.