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With this new layout, sparsehash will be used over default HashMap, sparsehash is more memory efficient but it is also slower. So in a nutshell: - HashMap uses ~2x more memory then sparse_hash_map - HashMap ~2-2.5x faster then sparse_hash_map (tested on lots of input, and the most close to production was dictionary with 600KK hashes and UInt16 as value) TODO: - fix allocated memory calculation - getBufferSizeInBytes/getBufferSizeInCells interface - benchmarks v0: replace HashMap with google::sparse_hash_map v2: use google::sparse_hash_map only when <sparse> isset to true v3: replace attributes with different layout v4: use ch hash over std::hash |
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| .. | ||
| external_dicts_dict_layout.md | ||
| external_dicts_dict_lifetime.md | ||
| external_dicts_dict_sources.md | ||
| external_dicts_dict_structure.md | ||
| external_dicts_dict.md | ||
| external_dicts.md | ||
| index.md | ||
| internal_dicts.md | ||