Performance optimizations for parsers#148
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Use skip/len tracking instead of byte-by-byte binary accumulation in parse_hd_value. This avoids O(n²) allocation overhead. Key changes: - Track original binary + skip position + length - Add 4-byte chunking for faster scanning - Separate fast path for single-segment vs folded headers - Use binary:part/3 only at boundaries Benchmark shows ~2.1x speedup for typical header blocks.
Add map-based indices for O(1) header lookup during encoding. Previously, finding a header in the dynamic table required O(n) linear scan. Now uses maps with sequence numbers. Key changes: - Add dyn_field_idx and dyn_name_idx maps to state record - Store sequence numbers; compute actual index via maps:size - Insert without eviction is O(1) (no map shifting needed) - Rebuild maps only on eviction (less frequent operation) - Add bench/0 for performance testing Lookup formula: index = 62 + (count - 1 - seq) Benchmark: 0.036 us/lookup with 50 dynamic entries.
Add map-based indices for O(1) header lookup during encoding, similar to the HPACK optimization. Key changes: - Add dyn_field_idx and dyn_name_idx maps to state record - Store absolute indices (which never change in QPACK) - Insert without eviction is O(1) - Rebuild maps only on eviction - Add bench/0 for performance testing Benchmark: 0.037 us/lookup with 50 dynamic entries.
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Summary
Results
All tests pass.