perf(parser): 4 targeted optimizations for NZB import pipeline#347
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perf(parser): 4 targeted optimizations for NZB import pipeline#347
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- Parallelize yEnc header fetches (2nd + last segment) in normalizeSegmentSizesWithYenc using errgroup.WithContext, cutting normalization wall time ~50% for files with 3+ segments - Pre-compile 4 obfuscation regex patterns in fileinfo as package-level vars, eliminating sync.Map lookups on every filename evaluation - Consolidate 4 binary.Read calls in PAR2 ReadFileDescriptor into a single fixed-struct read (56 bytes in one shot) - Replace 8-byte loop in HasMagicBytes with bytes.Equal for SIMD-backed comparison, consistent with fileinfo/detector.go style Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
drondeseries
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in drondeseries/altmount_old
Apr 16, 2026
- Parallelize yEnc header fetches (2nd + last segment) in normalizeSegmentSizesWithYenc using errgroup.WithContext, cutting normalization wall time ~50% for files with 3+ segments - Pre-compile 4 obfuscation regex patterns in fileinfo as package-level vars, eliminating sync.Map lookups on every filename evaluation - Consolidate 4 binary.Read calls in PAR2 ReadFileDescriptor into a single fixed-struct read (56 bytes in one shot) - Replace 8-byte loop in HasMagicBytes with bytes.Equal for SIMD-backed comparison, consistent with fileinfo/detector.go style Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
normalizeSegmentSizesWithYenc: 2nd and last segment fetches now run concurrently viaerrgroup.WithContext— ~50% wall-time reduction per file with 3+ segmentsfileinfo/fileinfo.go: 4 patterns promoted to package-level*regexp.Regexpvars, eliminatingsync.Maplookups on every filename evaluation (called 3× per file)binary.Readcalls inpar2/reader.go: 4 separate reads of the 56-byte FileDescriptor header collapsed into a single fixed-struct readbytes.EqualinHasMagicBytes(par2/detector.go): replaces manual 8-byte loop with SIMD-backedbytes.Equal, consistent withfileinfo/detector.gostyleTest plan
go build ./internal/importer/parser/...passesgo test ./internal/importer/parser/...passes (all existing tests green)🤖 Generated with Claude Code