Files
hakmem/core
Moe Charm (CI) 9a30a577e7 Perf optimization: Remove redundant memset in SuperSlab init
Problem: 4 memset() calls in superslab_allocate() consumed 23.83% CPU time
according to perf analysis (see PERF_ANALYSIS_EXECUTIVE_SUMMARY.md).

Root cause: mmap() already returns zero-initialized pages, making these
memset() calls redundant in production builds.

Solution: Comment out 4 memset() calls (lines 913-916):
- memset(ss->slabs, 0, ...)
- memset(ss->remote_heads, 0, ...)
- memset(ss->remote_counts, 0, ...)
- memset(ss->slab_listed, 0, ...)

Benchmark results (10M iterations × 5 runs, ws=256):
- Before: 71.86M ops/s (avg)
- After:  72.78M ops/s (avg)
- Improvement: +1.3% (+920K ops/s)

Note: Improvement is modest because this benchmark doesn't allocate many
new SuperSlabs. Greater impact expected in workloads with frequent
SuperSlab allocations or longer-running applications.

Perf analysis: commit 53bc92842
2025-11-28 17:57:00 +09:00
..
2025-11-11 21:49:05 +09:00