Arrow PyCapsule stream, pyarrow-free to_polars and Excel-compatible XLSB integers (v5.1.1) by GabrielMarquezMatte · Pull Request #134 · GabrielMarquezMatte/ExcelReader

GabrielMarquezMatte · 2026-09-30T20:50:11Z

Summary

Arrow PyCapsule stream (Python). Workbook.to_arrow_stream(schema, header_row=1, batch_size=10000)
returns an ArrowStream implementing __arrow_c_stream__, built with ctypes alone. Any consumer of
the Arrow PyCapsule interface takes it directly: pl.DataFrame(stream),
pyarrow.RecordBatchReader.from_stream(stream), pd.DataFrame.from_arrow(stream) (pandas 3).
The stream is single-use, and an unconsumed stream or a dropped capsule releases the native read.
to_polars() no longer needs pyarrow. With parallelism=1 (the default) it goes through
to_arrow_stream() and polars.DataFrame, still streamed and still chunked. parallelism other
than 1 keeps the whole-sheet path through to_record_batch(), which still requires pyarrow.
XLSB integers in RK's float form. The writer now encodes an integral number in BrtCellRk's
float form whenever it is exact (every integer up to ±524,288, so every date serial), which is what
Excel does. Before, it always used the int form. That is valid MS-XLSB, but calamine ignores a date
style on it, so polars.read_excel read our XLSB dates back as integers. Same 4-byte record; larger
integers still use the int form or BrtCellReal.
polars engine benchmark. python/benchmarks/bench_polars_engine.py compares excelreader against
polars.read_excel(engine="calamine") on plain XLSX/XLSB, and against msoffcrypto-tool + calamine on
encrypted files. It uses a fixed schema on both sides, checks the frames are equal before timing,
runs each case in a fresh subprocess and reports peak RSS. On 1M rows × 7 columns excelreader is
3.0–5.3x faster with 4–6x lower peak RSS (Windows, x64).

Housekeeping

rust/excelreader/build.rs finds lib.exe through cc::windows_registry, so building the import
library no longer needs a VS developer prompt (cc added as a build dependency).
rust/.cargo/config.toml points EXCELREADER_NATIVE_LIB_DIR at the Python package's _lib.
v5.1.0 public API promoted to PublicAPI.Shipped.txt.

Compatibility

No breaking changes. XL_ABI_VERSION stays 5, and there are no C ABI changes.
to_polars() returns the same frame as before.
XLSB files written before this change still read correctly in ExcelReader. Only third-party readers
that ignore the date style on int-form RK cells (calamine) benefit, and only for newly written files.

Test plan

dotnet test tests/ExcelReader.Tests: 2450 passed. Adds a theory pinning the RK form for
0, ±1, 45000 (float) and 524289, 536870911 (int).
pytest python/tests against a freshly built native library: 128 passed, 1 xfailed (pre-existing).
Adds tests for pl.DataFrame(to_arrow_stream()), single use, release when unconsumed, release on
a dropped capsule, and negative batch_size.
Checked against an XLSB saved by Excel: Excel writes integers in the float form, and calamine
reads those dates correctly.
bench_polars_engine.py --rows 1000000 --n 5 against excelreader-native 5.1.0; all cases verified equal.

…-api-v5.1.0 chore: promote public API for v5.1.0

…rrow_stream method in Workbook

…lReader into develop

Bumps OfficeIMO.Excel from 3.4.3 to 3.4.4 --- updated-dependencies: - dependency-name: OfficeIMO.Excel dependency-version: 3.4.4 dependency-type: direct:production update-type: version-update:semver-patch dependency-group: benchmarks ... Signed-off-by: dependabot[bot] <support@github.com>

…d corresponding tests

…ts/ExcelReader.Benchmarks/develop/benchmarks-f3f134d891 Bump the benchmarks group with 1 update

codecov-commenter · 2026-09-30T20:53:59Z

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Additional details and impacted files

@@            Coverage Diff             @@
##           master     #134      +/-   ##
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==========================================
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github-actions · 2026-09-30T20:58:03Z

Benchmark Results

Baseline: master 72c57812, from the series published by benchmark-pages.yml. Both sides ran on a shared ubuntu-latest runner, so treat anything under ±10% as noise.

Moved by at least 10%

Benchmark	master	This PR	Delta
`ExcelReader.Benchmarks.ParseBenchmark.OfficeIMO(Rows: 50000)`	89.88 ms	172.87 ms	+92.3%
`ExcelReader.Benchmarks.ChunkedParseBenchmark.WholeSheet(Rows: 50000)`	7.01 ms	13.43 ms	+91.6%
`ExcelReader.Benchmarks.ChunkedParseBenchmark.Batched_10k(Rows: 50000)`	7.05 ms	12.87 ms	+82.5%
`ExcelReader.Benchmarks.NativeTypedParseBenchmark.ParseTyped`	31.12 ms	52.37 ms	+68.3%
`ExcelReader.Benchmarks.NativeTypedParseBenchmark.ParseArrow`	31.34 ms	52.19 ms	+66.5%
`ExcelReader.Benchmarks.NativeRowReadBenchmark.NextRowDecoded`	37.21 ms	61.33 ms	+64.8%
`ExcelReader.Benchmarks.NativeRowReadBenchmark.ReadAllBlob`	35.93 ms	58.62 ms	+63.2%
`ExcelReader.Benchmarks.NativeRowReadBenchmark.NextRowBlob`	33.19 ms	53.00 ms	+59.7%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsx_ExcelReader_Prefetch`	32.80 ms	50.94 ms	+55.3%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Plain_Stream`	58.52 µs	89.13 µs	+52.3%
`ExcelReader.Benchmarks.ChunkedParseBenchmark.Batched_1k(Rows: 50000)`	8.63 ms	12.96 ms	+50.1%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Large_Encrypted_OpenOnly`	44.24 ms	64.45 ms	+45.7%
`ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark.EndToEnd_Prefetch(Rows: 65536)`	41.86 ms	59.61 ms	+42.4%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsx_ExcelReader_Memory_Prefetch`	33.35 ms	47.43 ms	+42.2%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsm_ExcelReader_Prefetch`	34.43 ms	46.98 ms	+36.4%
`ExcelReader.Benchmarks.CsvParallelVsSepBenchmark.ExcelReader_Sequential(Corpus: ConversionHeavy)`	506.97 ms	691.34 ms	+36.4%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Csv_ExcelReader_Materialized`	24.42 ms	33.25 ms	+36.2%
`ExcelReader.Benchmarks.CsvParallelVsSepBenchmark.ExcelReader_Sequential(Corpus: NarrowInt)`	388.68 ms	527.99 ms	+35.8%
`ExcelReader.Benchmarks.CsvParallelVsSepBenchmark.ExcelReader_Parallel(Corpus: NarrowInt)`	253.96 ms	342.30 ms	+34.8%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsx_Sylvan`	231.96 ms	312.40 ms	+34.7%
`ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark.EndToEnd(Rows: 65536)`	49.73 ms	66.06 ms	+32.8%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsm_Sylvan`	234.88 ms	311.03 ms	+32.4%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsx_Sylvan(Rows: 65536)`	219.73 ms	290.92 ms	+32.4%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsm_ExcelReader_Memory_Prefetch`	36.71 ms	48.58 ms	+32.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Csv_ExcelReader_Memory`	6.21 ms	8.22 ms	+32.3%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.ConversionHeavyAggregate(Dop: 16)`	262.07 ms	344.87 ms	+31.6%
`ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark.Stored_EndToEnd(Rows: 65536)`	23.72 ms	31.21 ms	+31.6%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowIntAggregate(Dop: 8)`	174.15 ms	228.54 ms	+31.2%
`ExcelReader.Benchmarks.RealDataTypedParseBenchmark.Xlsx_ExcelParser`	70.20 ms	91.06 ms	+29.7%
`ExcelReader.Benchmarks.XlsReadBenchmark.ExcelReaderAsync(Rows: 50000)`	3.01 ms	3.90 ms	+29.6%
`ExcelReader.Benchmarks.CsvParseBenchmark.Sep(Rows: 50000)`	6.90 ms	8.94 ms	+29.5%
`ExcelReader.Benchmarks.CsvParallelVsSepBenchmark.Sep_Sequential(Corpus: NarrowInt)`	353.44 ms	455.55 ms	+28.9%
`ExcelReader.Benchmarks.NativeRowReadBenchmark.ReadAllDecoded`	53.70 ms	69.02 ms	+28.5%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Encrypted_OpenOnly`	44.68 ms	57.37 ms	+28.4%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsx_ExcelReader_Memory`	59.71 ms	76.13 ms	+27.5%
`ExcelReader.Benchmarks.CsvReadBenchmark.Sylvan(Rows: 50000)`	3.38 ms	4.30 ms	+27.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xls_ExcelReader`	11.89 ms	15.13 ms	+27.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsx_ExcelReader`	59.89 ms	76.21 ms	+27.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsm_ExcelReader_Memory`	59.49 ms	75.62 ms	+27.1%
`ExcelReader.Benchmarks.XlsReadBenchmark.ExcelReader(Rows: 50000)`	3.01 ms	3.83 ms	+27.0%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsm_ExcelReader_Materialized`	62.33 ms	78.90 ms	+26.6%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsx_ExcelReader_Prefetch(Rows: 65536)`	40.40 ms	51.07 ms	+26.4%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowInt(Dop: 4)`	257.88 ms	325.75 ms	+26.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsm_ExcelReader`	60.67 ms	76.62 ms	+26.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Csv_ExcelReader`	6.53 ms	8.24 ms	+26.2%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Csv_Sylvan`	5.42 ms	6.83 ms	+26.0%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowInt(Dop: 16)`	245.58 ms	308.35 ms	+25.6%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsx_ExcelReader_Materialized`	62.77 ms	78.52 ms	+25.1%
`ExcelReader.Benchmarks.CsvParseBenchmark.ExcelParserAsync(Rows: 50000)`	3.98 ms	4.97 ms	+24.9%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsb_ExcelReader_Memory_Prefetch`	17.32 ms	21.61 ms	+24.7%
`ExcelReader.Benchmarks.ParseBenchmark.ExcelParserXlsbSync(Rows: 50000)`	6.68 ms	8.28 ms	+24.0%
`ExcelReader.Benchmarks.CsvReadBenchmark.ExcelReaderAsync(Rows: 50000)`	2.43 ms	3.02 ms	+24.0%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xls_ExcelReader_Memory`	11.99 ms	14.80 ms	+23.5%
`ExcelReader.Benchmarks.CsvParallelVsSepBenchmark.Sep_Parallel(Corpus: NarrowInt)`	328.18 ms	405.34 ms	+23.5%
`ExcelReader.Benchmarks.ReadBenchmark.OfficeIMO(Rows: 50000)`	140.56 ms	173.32 ms	+23.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsb_ExcelReader_Prefetch`	17.75 ms	21.86 ms	+23.2%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsb_ExcelReader_Prefetch(Rows: 65536)`	34.44 ms	42.39 ms	+23.1%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsx_ExcelReader(Rows: 65536)`	50.52 ms	62.17 ms	+23.1%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsb_ExcelReader(Rows: 65536)`	43.30 ms	53.13 ms	+22.7%
`ExcelReader.Benchmarks.XlsReadBenchmark.Sylvan(Rows: 50000)`	5.12 ms	6.27 ms	+22.4%
`ExcelReader.Benchmarks.CsvParseBenchmark.ExcelParserSync(Rows: 50000)`	3.89 ms	4.75 ms	+22.0%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowIntAggregate(Dop: 16)`	174.11 ms	212.27 ms	+21.9%
`ExcelReader.Benchmarks.CsvParallelVsSepBenchmark.Sep_Sequential(Corpus: ConversionHeavy)`	622.68 ms	757.82 ms	+21.7%
`ExcelReader.Benchmarks.CsvParallelVsSepBenchmark.ExcelReader_Parallel(Corpus: ConversionHeavy)`	276.43 ms	335.85 ms	+21.5%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsb_ExcelReader_Memory(Rows: 65536)`	42.60 ms	51.68 ms	+21.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xls_ExcelReader_Materialized`	14.34 ms	17.38 ms	+21.2%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Large_Encrypted_Stream`	102.75 ms	124.45 ms	+21.1%
`ExcelReader.Benchmarks.CsvReadBenchmark.Sep(Rows: 50000)`	7.76 ms	9.40 ms	+21.1%
`ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark.IndexParse_Utf8Parser(Rows: 65536)`	2.61 ms	3.16 ms	+21.0%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsb_Sylvan`	35.33 ms	42.46 ms	+20.2%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.ConversionHeavyAggregate(Dop: 8)`	257.62 ms	309.40 ms	+20.1%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.ConversionHeavy(Dop: 16)`	400.63 ms	480.51 ms	+19.9%
`ExcelReader.Benchmarks.RealDataTypedParseBenchmark.Xlsb_ExcelParser`	38.87 ms	46.41 ms	+19.4%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowInt(Dop: 1)`	435.29 ms	518.97 ms	+19.2%
`ExcelReader.Benchmarks.ParseBenchmark.ExcelParserAsync(Rows: 50000)`	9.77 ms	11.64 ms	+19.1%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsb_Sylvan(Rows: 65536)`	74.58 ms	88.69 ms	+18.9%
`ExcelReader.Benchmarks.ParseBenchmark.ExcelParserXlsbAsync(Rows: 50000)`	6.93 ms	8.23 ms	+18.8%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowInt(Dop: 2)`	384.17 ms	455.89 ms	+18.7%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsb_ExcelReader_Materialized_Interned(Rows: 65536)`	67.03 ms	79.53 ms	+18.7%
`ExcelReader.Benchmarks.ParseBenchmark.ExcelParserSync(Rows: 50000)`	9.47 ms	11.24 ms	+18.6%
`ExcelReader.Benchmarks.ReadBenchmark.ExcelReaderAsync(Rows: 50000)`	8.17 ms	9.69 ms	+18.6%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Large_Plain_Stream`	50.17 ms	59.38 ms	+18.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsb_ExcelReader`	29.45 ms	34.69 ms	+17.8%
`ExcelReader.Benchmarks.ParseBenchmark.RefStructModelSync(Rows: 50000)`	8.07 ms	9.50 ms	+17.8%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.ConversionHeavyAggregate(Dop: 4)`	271.73 ms	319.07 ms	+17.4%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xls_Sylvan`	21.73 ms	25.49 ms	+17.3%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsb_ExcelReader_Memory`	29.44 ms	34.49 ms	+17.2%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Encrypted_Stream`	49.86 ms	58.34 ms	+17.0%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Encrypted_Stream_VerifyIntegrity`	50.03 ms	58.53 ms	+17.0%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsx_ExcelReader_Materialized_Interned(Rows: 65536)`	76.41 ms	88.70 ms	+16.1%
`ExcelReader.Benchmarks.ReadBenchmark.Sylvan(Rows: 50000)`	35.33 ms	40.92 ms	+15.8%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowIntAggregate(Dop: 1)`	367.58 ms	425.44 ms	+15.7%
`ExcelReader.Benchmarks.CsvParseBenchmark.Sylvan(Rows: 50000)`	9.83 ms	11.35 ms	+15.4%
`ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark.IndexParse_DigitLoop(Rows: 65536)`	1.63 ms	1.88 ms	+15.3%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsx_ExcelReader_Materialized(Rows: 65536)`	77.69 ms	89.57 ms	+15.3%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowIntAggregate(Dop: 2)`	272.51 ms	314.08 ms	+15.3%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowIntAggregate(Dop: 4)`	164.53 ms	189.60 ms	+15.2%
`ExcelReader.Benchmarks.EncryptedWorkbookBenchmark.Encrypted_Memory`	50.11 ms	57.66 ms	+15.1%
`ExcelReader.Benchmarks.ParseBenchmark.ExcelParserStructSync(Rows: 50000)`	9.11 ms	10.46 ms	+14.8%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.ConversionHeavy(Dop: 8)`	402.09 ms	461.48 ms	+14.8%
`ExcelReader.Benchmarks.ReadBenchmark.ExcelReader(Rows: 50000)`	7.72 ms	8.82 ms	+14.3%
`ExcelReader.Benchmarks.ReadBenchmark.ExcelReaderMaterialized(Rows: 50000)`	9.02 ms	10.30 ms	+14.2%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.ConversionHeavy(Dop: 1)`	804.00 ms	918.13 ms	+14.2%
`ExcelReader.Benchmarks.ParseBenchmark.ExcelParserSyncSharedStrings(Rows: 50000)`	9.24 ms	10.41 ms	+12.7%
`ExcelReader.Benchmarks.RealDataReadBenchmark.Xlsb_ExcelReader_Materialized`	32.85 ms	36.96 ms	+12.5%
`ExcelReader.Benchmarks.CsvReadBenchmark.ExcelReader(Rows: 50000)`	4.42 ms	4.95 ms	+11.9%
`ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark.SharedStringPrologue(Rows: 65536)`	17.81 ms	19.88 ms	+11.7%
`ExcelReader.Benchmarks.StringHeavyReadBenchmark.Xlsb_ExcelReader_Materialized(Rows: 65536)`	70.75 ms	78.92 ms	+11.5%
`ExcelReader.Benchmarks.CsvReadBenchmark.ExcelReaderWide(Rows: 50000)`	8.52 ms	9.39 ms	+10.2%
`ExcelReader.Benchmarks.CsvParallelParseBenchmark.NarrowInt(Dop: 8)`	265.20 ms	291.88 ms	+10.1%
`ExcelReader.Benchmarks.ArrowConversionBenchmark.CsvAllString(Rows: 100000)`	31.42 ms	27.88 ms	-11.3%
`ExcelReader.Benchmarks.DataReaderBenchmark.Baseline_RawRows(Rows: 50000)`	10.83 ms	9.49 ms	-12.4%
`ExcelReader.Benchmarks.ArrowConversionBenchmark.CsvTypedWithInference(Rows: 100000)`	17.47 ms	14.64 ms	-16.2%

46 within ±10%.

Full results per group

ExcelReader.Benchmarks.ArrowConversionBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 9V74 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
CsvAllString	100000	27.88 ms	1.175 ms	0.305 ms	1.00	0.01	687.5000	562.5000	562.5000	16.27 MB	1.00
CsvTyped	100000	13.81 ms	0.931 ms	0.144 ms	0.50	0.01	421.8750	375.0000	375.0000	8.13 MB	0.50
XlsbTyped	100000	22.87 ms	3.315 ms	0.861 ms	0.82	0.03	375.0000	343.7500	343.7500	8.15 MB	0.50
CsvTypedWithInference	100000	14.64 ms	1.068 ms	0.165 ms	0.53	0.01	656.2500	593.7500	593.7500	14.89 MB	0.92

ExcelReader.Benchmarks.ChunkedParseBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	Gen0	Gen1	Allocated	Alloc Ratio
WholeSheet	50000	13.43 ms	0.202 ms	0.053 ms	1.00	78.1250	62.5000	1.31 MB	1.00
Batched_10k	50000	12.87 ms	0.244 ms	0.063 ms	0.96	93.7500	46.8750	1.6 MB	1.23
Batched_1k	50000	12.96 ms	0.051 ms	0.013 ms	0.96	93.7500	-	1.52 MB	1.16

ExcelReader.Benchmarks.ColdStartBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-GOEFXF : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

InvocationCount=1  IterationCount=1  LaunchCount=16  
RunStrategy=ColdStart  UnrollFactor=1  WarmupCount=0

Method	Rows	Mean	Error	StdDev	Allocated
TypedParseFirstUse	200	42.03 ms	0.323 ms	0.317 ms	28.43 KB
RecordWriteFirstUse	200	24.70 ms	0.253 ms	0.248 ms	84.25 KB
FluentParseFirstUse	200	36.14 ms	0.541 ms	0.532 ms	30.95 KB
FluentParseWithAttributeFallbackFirstUse	200	45.64 ms	0.635 ms	0.624 ms	32.65 KB

ExcelReader.Benchmarks.CsvParallelParseBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
Intel Xeon 6973P-C 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Dop	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
ConversionHeavy	1	918.1 ms	69.59 ms	10.77 ms	1.00	0.01	8000.0000	-	687048.53 KB	1.000
NarrowInt	1	519.0 ms	22.79 ms	3.53 ms	0.57	0.01	3000.0000	-	251159.83 KB	0.366
ConversionHeavyAggregate	1	686.2 ms	33.41 ms	8.68 ms	0.75	0.01	-	-	827.41 KB	0.001
NarrowIntAggregate	1	425.4 ms	42.98 ms	6.65 ms	0.46	0.01	-	-	814.81 KB	0.001

ConversionHeavy	2	642.9 ms	105.04 ms	27.28 ms	1.00	0.05	8000.0000	3000.0000	694949.95 KB	1.000
NarrowInt	2	455.9 ms	39.34 ms	6.09 ms	0.71	0.03	3000.0000	-	259138.2 KB	0.373
ConversionHeavyAggregate	2	496.1 ms	73.68 ms	11.40 ms	0.77	0.03	-	-	1306.26 KB	0.002
NarrowIntAggregate	2	314.1 ms	51.40 ms	13.35 ms	0.49	0.03	-	-	1241.3 KB	0.002

ConversionHeavy	4	443.9 ms	46.53 ms	12.08 ms	1.00	0.04	8000.0000	7000.0000	695106.34 KB	1.000
NarrowInt	4	325.8 ms	20.52 ms	5.33 ms	0.73	0.02	3000.0000	500.0000	259421.09 KB	0.373
ConversionHeavyAggregate	4	319.1 ms	85.85 ms	22.30 ms	0.72	0.05	-	-	1292.6 KB	0.002
NarrowIntAggregate	4	189.6 ms	7.58 ms	1.97 ms	0.43	0.01	-	-	1249.79 KB	0.002

ConversionHeavy	8	461.5 ms	77.02 ms	20.00 ms	1.00	0.06	8000.0000	7000.0000	695192.07 KB	1.000
NarrowInt	8	291.9 ms	64.03 ms	9.91 ms	0.63	0.03	3000.0000	1000.0000	259564.42 KB	0.373
ConversionHeavyAggregate	8	309.4 ms	26.08 ms	6.77 ms	0.67	0.03	-	-	1269.37 KB	0.002
NarrowIntAggregate	8	228.5 ms	47.74 ms	12.40 ms	0.50	0.03	-	-	1325.28 KB	0.002

ConversionHeavy	16	480.5 ms	48.86 ms	12.69 ms	1.00	0.03	8000.0000	4000.0000	695497.34 KB	1.000
NarrowInt	16	308.4 ms	88.21 ms	13.65 ms	0.64	0.03	3000.0000	1000.0000	259522.64 KB	0.373
ConversionHeavyAggregate	16	344.9 ms	18.57 ms	2.87 ms	0.72	0.02	-	-	1322.37 KB	0.002
NarrowIntAggregate	16	212.3 ms	13.32 ms	3.46 ms	0.44	0.01	-	-	1336.03 KB	0.002

ExcelReader.Benchmarks.CsvParallelVsSepBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
Intel Xeon 6973P-C 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Corpus	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
ExcelReader_Sequential	NarrowInt	528.0 ms	10.88 ms	1.68 ms	1.00	0.00	3000.0000	-	244.14 MB	1.00
ExcelReader_Parallel	NarrowInt	342.3 ms	91.33 ms	23.72 ms	0.65	0.04	3000.0000	1000.0000	253.15 MB	1.04
Sep_Sequential	NarrowInt	455.6 ms	10.05 ms	2.61 ms	0.86	0.01	3000.0000	-	244.15 MB	1.00
Sep_Parallel	NarrowInt	405.3 ms	20.66 ms	5.37 ms	0.77	0.01	3000.0000	1000.0000	255.93 MB	1.05

ExcelReader_Sequential	ConversionHeavy	691.3 ms	29.96 ms	7.78 ms	1.00	0.01	5000.0000	-	467.3 MB	1.00
ExcelReader_Parallel	ConversionHeavy	335.9 ms	14.88 ms	2.30 ms	0.49	0.01	5000.0000	4000.0000	473.63 MB	1.01
Sep_Sequential	ConversionHeavy	757.8 ms	21.24 ms	5.52 ms	1.10	0.01	5000.0000	-	467.31 MB	1.00
Sep_Parallel	ConversionHeavy	533.6 ms	84.73 ms	22.00 ms	0.77	0.03	5000.0000	4000.0000	476.42 MB	1.02

ExcelReader.Benchmarks.CsvParseBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
Intel Xeon 6973P-C 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
ExcelParserSync	50000	4.752 ms	0.1105 ms	0.0287 ms	1.00	0.01	46.8750	-	3.86 MB	1.00
ExcelParserAsync	50000	4.971 ms	0.2424 ms	0.0630 ms	1.05	0.01	46.8750	-	3.86 MB	1.00
Sep	50000	8.941 ms	0.4135 ms	0.1074 ms	1.88	0.02	46.8750	-	3.87 MB	1.00
Sylvan	50000	11.349 ms	0.3848 ms	0.0595 ms	2.39	0.02	125.0000	15.6250	10.95 MB	2.84

ExcelReader.Benchmarks.CsvReadBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 9V74 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	Allocated	Alloc Ratio
ExcelReader	50000	4.946 ms	0.0123 ms	0.0032 ms	1.00	448 B	1.00
ExcelReaderWide	50000	9.391 ms	0.0705 ms	0.0109 ms	1.90	376 B	0.84
ExcelReaderAsync	50000	3.018 ms	0.0291 ms	0.0076 ms	0.61	520 B	1.16
Sep	50000	9.395 ms	0.0857 ms	0.0222 ms	1.90	4024 B	8.98
Sylvan	50000	4.305 ms	0.0201 ms	0.0052 ms	0.87	38682 B	86.34

ExcelReader.Benchmarks.CsvWriteBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
ExcelReaderWriter	50000	6.348 ms	0.6018 ms	0.1563 ms	1.00	0.03	500.0000	500.0000	500.0000	4 MB	1.00
Sep	50000	10.161 ms	1.3596 ms	0.3531 ms	1.60	0.06	500.0000	500.0000	500.0000	4.01 MB	1.00
SylvanWriter	50000	10.431 ms	0.3478 ms	0.0903 ms	1.64	0.04	500.0000	500.0000	500.0000	4.04 MB	1.01

ExcelReader.Benchmarks.DataReaderBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 9V74 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
Baseline_RawRows	50000	9.485 ms	0.2807 ms	0.0729 ms	1.00	0.01	-	-	-	11.18 KB	1.00
DataReader_GetValue	50000	13.244 ms	0.1732 ms	0.0268 ms	1.40	0.01	312.5000	-	-	5138.82 KB	459.66
DataReader_TypedGetters	50000	14.102 ms	0.2098 ms	0.0545 ms	1.49	0.01	93.7500	-	-	1623.2 KB	145.19
DataReader_GetBytes	50000	10.129 ms	0.2961 ms	0.0458 ms	1.07	0.01	-	-	-	11.87 KB	1.06
DataTable_Load	50000	77.478 ms	9.8075 ms	2.5470 ms	8.17	0.25	2000.0000	1857.1429	857.1429	23400.49 KB	2,093.13

ExcelReader.Benchmarks.EncryptedWorkbookBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 9V74 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Allocated	Alloc Ratio
Plain_Stream	89.13 μs	62.52 μs	16.24 μs	1.02	0.23	0.9766	19.42 KB	1.00
Encrypted_Stream	58,338.18 μs	1,962.55 μs	509.67 μs	670.02	97.95	-	48.32 KB	2.49
Encrypted_Stream_VerifyIntegrity	58,528.35 μs	698.08 μs	108.03 μs	672.20	98.64	-	50.26 KB	2.59
Encrypted_Memory	57,660.08 μs	788.65 μs	122.04 μs	662.23	97.18	-	52.75 KB	2.72
Encrypted_OpenOnly	57,374.92 μs	415.70 μs	64.33 μs	658.95	96.69	-	42.8 KB	2.20
Large_Plain_Stream	59,376.99 μs	799.76 μs	123.76 μs	681.95	100.07	-	11.18 KB	0.58
Large_Encrypted_Stream	124,447.01 μs	12,488.41 μs	3,243.20 μs	1,429.28	211.44	-	36.94 KB	1.90
Large_Encrypted_OpenOnly	64,450.62 μs	913.23 μs	141.32 μs	740.22	108.62	-	36.38 KB	1.87

ExcelReader.Benchmarks.NativeRowReadBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Mean	Error	StdDev	Ratio	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
NextRowBlob	53.00 ms	0.943 ms	0.245 ms	1.00	300.0000	300.0000	300.0000	3.71 MB	1.00
NextRowDecoded	61.33 ms	0.363 ms	0.094 ms	1.16	222.2222	222.2222	222.2222	3.71 MB	1.00
ReadAllBlob	58.62 ms	0.767 ms	0.119 ms	1.11	1000.0000	888.8889	-	21.06 MB	5.68
ReadAllDecoded	69.02 ms	2.490 ms	0.647 ms	1.30	500.0000	500.0000	500.0000	5.71 MB	1.54

ExcelReader.Benchmarks.NativeTypedParseBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Mean	Error	StdDev	Ratio	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
ParseTyped	52.37 ms	0.134 ms	0.035 ms	1.00	700.0000	500.0000	300.0000	11.61 MB	1.00
ParseArrow	52.19 ms	0.753 ms	0.196 ms	1.00	700.0000	500.0000	300.0000	11.62 MB	1.00

ExcelReader.Benchmarks.ParseBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
Intel Xeon 6973P-C 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Allocated	Alloc Ratio
ExcelParserSync	50000	11.236 ms	0.6208 ms	0.1612 ms	1.00	0.02	46.8750	3966.8 KB	1.000
ExcelParserSyncSharedStrings	50000	10.412 ms	0.7788 ms	0.1205 ms	0.93	0.02	15.6250	2357.3 KB	0.594
ExcelParserStructSync	50000	10.461 ms	0.6859 ms	0.1781 ms	0.93	0.02	15.6250	1623.05 KB	0.409
RefStructModelSync	50000	9.501 ms	0.3742 ms	0.0972 ms	0.85	0.01	-	11.72 KB	0.003
ExcelParserAsync	50000	11.643 ms	0.3288 ms	0.0854 ms	1.04	0.02	46.8750	3968.95 KB	1.001
ExcelParserXlsbSync	50000	8.278 ms	1.4157 ms	0.3676 ms	0.74	0.03	46.8750	3968.9 KB	1.001
ExcelParserXlsbAsync	50000	8.231 ms	1.7207 ms	0.4469 ms	0.73	0.04	46.8750	3971.47 KB	1.001
OfficeIMO	50000	172.870 ms	151.0381 ms	39.2241 ms	15.39	3.19	-	5833.8 KB	1.471
Sylvan	50000	53.250 ms	4.9146 ms	1.2763 ms	4.74	0.12	100.0000	10726.41 KB	2.704
SylvanAsync	50000	57.143 ms	11.0658 ms	2.8738 ms	5.09	0.24	100.0000	10735.13 KB	2.706

ExcelReader.Benchmarks.ReadBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 9V74 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Allocated	Alloc Ratio
ExcelReader	50000	8.817 ms	0.0188 ms	0.0049 ms	1.00	0.00	-	11.18 KB	1.00
ExcelReaderAsync	50000	9.689 ms	0.0214 ms	0.0056 ms	1.10	0.00	-	13.31 KB	1.19
ExcelReaderXlsb	50000	5.640 ms	0.0140 ms	0.0036 ms	0.64	0.00	-	13.28 KB	1.19
ExcelReaderXlsbAsync	50000	5.951 ms	0.0701 ms	0.0182 ms	0.67	0.00	-	15.84 KB	1.42
ExcelReaderMaterialized	50000	10.302 ms	0.0268 ms	0.0042 ms	1.17	0.00	93.7500	1622.51 KB	145.13
Sylvan	50000	40.923 ms	0.6319 ms	0.0978 ms	4.64	0.01	76.9231	1939.18 KB	173.46
OfficeIMO	50000	173.315 ms	205.1407 ms	31.7457 ms	19.66	3.20	-	7003.67 KB	626.46
OfficeIMOXlsb	50000	12.385 ms	0.3184 ms	0.0827 ms	1.40	0.01	406.2500	6858.69 KB	613.50

ExcelReader.Benchmarks.RealDataReadBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
Intel Xeon Platinum 8370C CPU 2.80GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Allocated	Alloc Ratio
Xlsx_ExcelReader	76.215 ms	1.3918 ms	0.2154 ms	1.00	0.00	-	18288 B	1.00
Xlsx_Sylvan	312.399 ms	2.1761 ms	0.5651 ms	4.10	0.01	-	659568 B	36.07
Xlsx_ExcelReader_Materialized	78.521 ms	0.3150 ms	0.0487 ms	1.03	0.00	-	27984 B	1.53
Xlsx_ExcelReader_Prefetch	50.944 ms	13.9726 ms	3.6286 ms	0.67	0.04	-	38291 B	2.09
Xlsx_ExcelReader_Memory	76.131 ms	0.3606 ms	0.0937 ms	1.00	0.00	-	7176 B	0.39
Xlsx_ExcelReader_Memory_Prefetch	47.425 ms	6.0749 ms	1.5776 ms	0.62	0.02	-	27182 B	1.49
Xlsm_ExcelReader	76.619 ms	0.2432 ms	0.0632 ms	1.01	0.00	-	18288 B	1.00
Xlsm_Sylvan	311.034 ms	5.2077 ms	0.8059 ms	4.08	0.01	-	659648 B	36.07
Xlsm_ExcelReader_Materialized	78.897 ms	0.4375 ms	0.1136 ms	1.04	0.00	-	27984 B	1.53
Xlsm_ExcelReader_Prefetch	46.978 ms	7.2443 ms	1.8813 ms	0.62	0.02	-	38751 B	2.12
Xlsm_ExcelReader_Memory	75.620 ms	0.2487 ms	0.0385 ms	0.99	0.00	-	7176 B	0.39
Xlsm_ExcelReader_Memory_Prefetch	48.582 ms	10.7240 ms	2.7850 ms	0.64	0.03	-	27152 B	1.48
Xlsb_ExcelReader	34.687 ms	0.1605 ms	0.0417 ms	0.46	0.00	-	19256 B	1.05
Xlsb_Sylvan	42.459 ms	0.3750 ms	0.0580 ms	0.56	0.00	-	346673 B	18.96
Xlsb_ExcelReader_Materialized	36.962 ms	0.1186 ms	0.0183 ms	0.48	0.00	-	28952 B	1.58
Xlsb_ExcelReader_Prefetch	21.857 ms	5.1705 ms	0.8001 ms	0.29	0.01	-	44357 B	2.43
Xlsb_ExcelReader_Memory	34.487 ms	0.1074 ms	0.0279 ms	0.45	0.00	-	8896 B	0.49
Xlsb_ExcelReader_Memory_Prefetch	21.610 ms	2.6550 ms	0.6895 ms	0.28	0.01	-	29898 B	1.63
Xls_ExcelReader	15.128 ms	0.2202 ms	0.0572 ms	0.20	0.00	-	11576 B	0.63
Xls_Sylvan	25.491 ms	0.2402 ms	0.0624 ms	0.33	0.00	-	190366 B	10.41
Xls_ExcelReader_Materialized	17.382 ms	0.0687 ms	0.0178 ms	0.23	0.00	-	21272 B	1.16
Xls_ExcelReader_Memory	14.804 ms	0.0474 ms	0.0073 ms	0.19	0.00	-	11576 B	0.63
Csv_ExcelReader	8.239 ms	0.2236 ms	0.0581 ms	0.11	0.00	-	376 B	0.02
Csv_Sylvan	6.830 ms	0.0747 ms	0.0194 ms	0.09	0.00	-	41226 B	2.25
Csv_ExcelReader_Materialized	33.249 ms	1.8567 ms	0.4822 ms	0.44	0.01	1466.6667	37442984 B	2,047.41
Csv_ExcelReader_Memory	8.220 ms	0.2131 ms	0.0553 ms	0.11	0.00	-	312 B	0.02

ExcelReader.Benchmarks.RealDataTypedParseBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
Intel Xeon Platinum 8370C CPU 2.80GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Mean	Error	StdDev	Ratio	Gen0	Allocated	Alloc Ratio
Xlsx_ExcelParser	91.06 ms	0.771 ms	0.119 ms	1.00	333.3333	8.03 MB	1.00
Xlsb_ExcelParser	46.41 ms	0.171 ms	0.044 ms	0.51	272.7273	8.03 MB	1.00

ExcelReader.Benchmarks.RecordWriteBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
Xlsx	50000	16.891 ms	2.0456 ms	0.5312 ms	1.00	0.04	500.0000	500.0000	500.0000	4.02 MB	1.00
Xlsb	50000	10.412 ms	0.2459 ms	0.0639 ms	0.62	0.02	500.0000	500.0000	500.0000	4.02 MB	1.00
Xls	50000	7.297 ms	0.2770 ms	0.0429 ms	0.43	0.01	273.4375	273.4375	273.4375	4.03 MB	1.00
Csv	50000	6.498 ms	0.4180 ms	0.1086 ms	0.38	0.01	500.0000	500.0000	500.0000	4 MB	1.00
XlsxMapped	50000	19.643 ms	1.8236 ms	0.4736 ms	1.16	0.04	500.0000	500.0000	500.0000	4.02 MB	1.00
XlsbMapped	50000	11.646 ms	0.6850 ms	0.1060 ms	0.69	0.02	500.0000	500.0000	500.0000	4.02 MB	1.00
CsvMapped	50000	8.199 ms	0.2785 ms	0.0723 ms	0.49	0.01	500.0000	500.0000	500.0000	4 MB	1.00

ExcelReader.Benchmarks.StringHeavyReadBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
Xlsx_ExcelReader	65536	62.17 ms	0.411 ms	0.107 ms	1.00	0.00	-	-	-	2.19 MB	1.00
Xlsx_ExcelReader_Prefetch	65536	51.07 ms	19.639 ms	3.039 ms	0.82	0.04	-	-	-	2.25 MB	1.03
Xlsx_Sylvan	65536	290.92 ms	8.839 ms	2.296 ms	4.68	0.03	500.0000	-	-	17.41 MB	7.96
Xlsx_ExcelReader_Materialized	65536	89.57 ms	9.042 ms	2.348 ms	1.44	0.03	833.3333	666.6667	166.6667	15.26 MB	6.97
Xlsx_ExcelReader_Materialized_Interned	65536	88.70 ms	4.716 ms	0.730 ms	1.43	0.01	833.3333	666.6667	166.6667	15.27 MB	6.98
Xlsb_ExcelReader	65536	53.13 ms	0.209 ms	0.032 ms	0.85	0.00	-	-	-	2.19 MB	1.00
Xlsb_ExcelReader_Prefetch	65536	42.39 ms	8.057 ms	1.247 ms	0.68	0.02	-	-	-	2.3 MB	1.05
Xlsb_Sylvan	65536	88.69 ms	8.172 ms	2.122 ms	1.43	0.03	1166.6667	1000.0000	333.3333	17.38 MB	7.94
Xlsb_ExcelReader_Materialized	65536	78.92 ms	3.392 ms	0.881 ms	1.27	0.01	1000.0000	857.1429	285.7143	15.26 MB	6.97
Xlsb_ExcelReader_Materialized_Interned	65536	79.53 ms	3.158 ms	0.820 ms	1.28	0.01	1000.0000	857.1429	285.7143	15.27 MB	6.98
Xlsb_ExcelReader_Memory	65536	51.68 ms	1.296 ms	0.201 ms	0.83	0.00	-	-	-	6.47 MB	2.95

ExcelReader.Benchmarks.WriteBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
ExcelReaderWriter	50000	15.643 ms	1.6883 ms	0.4385 ms	1.00	0.04	500.0000	500.0000	500.0000	4.02 MB	1.00
ExcelReaderWriterSharedStrings	50000	15.366 ms	0.4478 ms	0.0693 ms	0.98	0.03	500.0000	500.0000	500.0000	4.06 MB	1.01
ExcelReaderWriterPrefetch	50000	12.856 ms	2.0626 ms	0.5356 ms	0.82	0.04	484.3750	484.3750	484.3750	4.03 MB	1.00
ExcelReaderXlsbWriter	50000	10.400 ms	0.6271 ms	0.1629 ms	0.67	0.02	500.0000	500.0000	500.0000	4.02 MB	1.00
ExcelReaderXlsbWriterSharedStrings	50000	10.040 ms	0.6906 ms	0.1794 ms	0.64	0.02	500.0000	500.0000	500.0000	4.06 MB	1.01
ExcelReaderXlsbWriterPrefetch	50000	8.883 ms	0.3060 ms	0.0795 ms	0.57	0.02	484.3750	484.3750	484.3750	4.03 MB	1.00
OfficeIMO	50000	24.351 ms	0.6916 ms	0.1796 ms	1.56	0.04	312.5000	312.5000	312.5000	4.02 MB	1.00
SpreadCheetah	50000	20.761 ms	0.2317 ms	0.0602 ms	1.33	0.03	1437.5000	718.7500	718.7500	15.84 MB	3.94

ExcelReader.Benchmarks.WritePathBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Mean	Error	StdDev	Allocated
NativeStrings_Xlsx	27.913 ms	0.1688 ms	0.0261 ms	18448 B
NativeStrings_Csv	7.250 ms	0.0460 ms	0.0071 ms	416 B
ArrowStrings_Xlsx	36.617 ms	0.2042 ms	0.0530 ms	18496 B
StyledRows_Xlsx	10.110 ms	0.3763 ms	0.0582 ms	18632 B

ExcelReader.Benchmarks.XlsReadBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 9V74 2.60GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v4

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	Gen0	Gen1	Allocated	Alloc Ratio
ExcelReader	50000	3.827 ms	0.0085 ms	0.0022 ms	1.00	-	-	2.45 KB	1.00
ExcelReaderAsync	50000	3.902 ms	0.0490 ms	0.0127 ms	1.02	-	-	2.52 KB	1.03
Sylvan	50000	6.266 ms	0.1112 ms	0.0289 ms	1.64	101.5625	23.4375	1717.73 KB	700.22
OfficeIMO	50000	7.276 ms	0.0366 ms	0.0095 ms	1.90	640.6250	-	10499.25 KB	4,279.95

ExcelReader.Benchmarks.XlsWriteBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
XlsWriter	50000	7.852 ms	0.1202 ms	0.0312 ms	1.00	484.3750	484.3750	484.3750	16.03 MB	1.00
XlsxWriter	50000	16.101 ms	0.3310 ms	0.0859 ms	2.05	500.0000	500.0000	500.0000	4.02 MB	0.25

ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark


BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.5 LTS (Noble Numbat)
AMD EPYC 7763 2.45GHz, 1 CPU, 4 logical and 2 physical cores
.NET SDK 10.0.401
  [Host]     : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3
  Job-MEHJPP : .NET 10.0.12 (10.0.12, 10.0.1226.42308), X64 RyuJIT x86-64-v3

IterationCount=5  WarmupCount=1

Method	Rows	Mean	Error	StdDev	Ratio	RatioSD	Allocated	Alloc Ratio
EndToEnd	65536	66.059 ms	2.0276 ms	0.5266 ms	1.00	0.01	2294168 B	1.00
EndToEnd_Prefetch	65536	59.611 ms	20.0746 ms	5.2133 ms	0.90	0.07	2388616 B	1.04
SharedStringPrologue	65536	19.882 ms	0.0864 ms	0.0224 ms	0.30	0.00	773304 B	0.34
Stored_EndToEnd	65536	31.208 ms	0.2662 ms	0.0691 ms	0.47	0.00	2293088 B	1.00
Stored_SharedStringPrologue	65536	4.812 ms	0.0492 ms	0.0128 ms	0.07	0.00	772224 B	0.34
IndexParse_Utf8Parser	65536	3.165 ms	0.0249 ms	0.0065 ms	0.05	0.00	-	0.00
IndexParse_DigitLoop	65536	1.880 ms	0.0080 ms	0.0021 ms	0.03	0.00	-	0.00

GabrielMarquezMatte and others added 8 commits September 28, 2026 19:20

chore: promote public API for v5.1.0

813afb1

Merge pull request #132 from GabrielMarquezMatte/chore/promote-public…

fe6d79a

…-api-v5.1.0 chore: promote public API for v5.1.0

feat: implement ArrowStream for efficient data streaming and add to_a…

dd14d31

…rrow_stream method in Workbook

Merge branch 'develop' of https://github.com/GabrielMarquezMatte/Exce…

97a04b2

…lReader into develop

feat: enhance XLSB writer to use float form for exact integers and ad…

3dc1ec4

…d corresponding tests

Merge pull request #133 from GabrielMarquezMatte/dependabot/nuget/tes…

672a012

…ts/ExcelReader.Benchmarks/develop/benchmarks-f3f134d891 Bump the benchmarks group with 1 update

Merge branch 'master' into develop

63e98f5

GabrielMarquezMatte merged commit fe522c5 into master Sep 30, 2026
58 checks passed

Conversation

GabrielMarquezMatte commented Sep 30, 2026

Summary

Housekeeping

Compatibility

Test plan

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codecov-commenter commented Sep 30, 2026

Codecov Report

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github-actions Bot commented Sep 30, 2026

Benchmark Results

Moved by at least 10%

ExcelReader.Benchmarks.ArrowConversionBenchmark

ExcelReader.Benchmarks.ChunkedParseBenchmark

ExcelReader.Benchmarks.ColdStartBenchmark

ExcelReader.Benchmarks.CsvParallelParseBenchmark

ExcelReader.Benchmarks.CsvParallelVsSepBenchmark

ExcelReader.Benchmarks.CsvParseBenchmark

ExcelReader.Benchmarks.CsvReadBenchmark

ExcelReader.Benchmarks.CsvWriteBenchmark

ExcelReader.Benchmarks.DataReaderBenchmark

ExcelReader.Benchmarks.EncryptedWorkbookBenchmark

ExcelReader.Benchmarks.NativeRowReadBenchmark

ExcelReader.Benchmarks.NativeTypedParseBenchmark

ExcelReader.Benchmarks.ParseBenchmark

ExcelReader.Benchmarks.ReadBenchmark

ExcelReader.Benchmarks.RealDataReadBenchmark

ExcelReader.Benchmarks.RealDataTypedParseBenchmark

ExcelReader.Benchmarks.RecordWriteBenchmark

ExcelReader.Benchmarks.StringHeavyReadBenchmark

ExcelReader.Benchmarks.WriteBenchmark

ExcelReader.Benchmarks.WritePathBenchmark

ExcelReader.Benchmarks.XlsReadBenchmark

ExcelReader.Benchmarks.XlsWriteBenchmark

ExcelReader.Benchmarks.XlsxSharedStringHotPathBenchmark

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