SUZUKI Sosuke
|
f01467d3dc
|
perf(buffer): optimize Buffer.from(array) by using setFromArrayLike directly (#26135)
## Summary
Optimizes `Buffer.from(array)` by bypassing `JSC::construct()` overhead
(~30ns) and leveraging JSC's internal array optimizations.
## Changes
- For JSArray inputs, directly use `setFromArrayLike()` which internally
detects array indexing types (Int32Shape/DoubleShape) and uses bulk copy
operations (`copyFromInt32ShapeArray`/`copyFromDoubleShapeArray`)
- Array-like objects and iterables continue to use the existing slow
path
- Added mitata benchmark for measuring performance
## Benchmark Results
| Test | Before | After | Improvement |
|------|--------|-------|-------------|
| Buffer.from(int32[8]) | ~85ns | ~43ns | ~50% faster |
| Buffer.from(int32[64]) | ~207ns | ~120ns | ~42% faster |
| Buffer.from(int32[1024]) | ~1.85μs | ~1.32μs | ~29% faster |
| Buffer.from(double[8]) | ~86ns | ~50ns | ~42% faster |
| Buffer.from(double[64]) | ~212ns | ~151ns | ~29% faster |
Bun is now faster than Node.js for these operations.
## Test
All 449 buffer tests pass.
|
2026-01-15 12:10:47 -08:00 |
|