Enable HNSW index arrays with transparent huge pages - #72
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TamimEhsan
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TamimEhsan
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This PR enables hugepage if the device setting is set to madvise mode. The groundwork was already there in the library.
data_level0_memory_is ~1.28 GiB and every candidate visit is a random access into it. With THP inmadvisemode a plainmallocgets no huge pages, so that array sits on ~335,000 4 KiB pages against a ~2048-entry STLB — nearly every visit misses and takes a page walk. The hugepage size is set to 2MB.The gain exists because this host is in
madvisemode. On a host set toalwaysit is already there without the patch; onnever,MADV_HUGEPAGEis ignored and it fallbacks to original behaviour.Benchmarks
dataset: GIST1M, topk = 10