Slow performance for AdjustToContents() on large row numers

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Do you want to request a feature or report a bug?

• Bug
• Feature
• Question

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• Yes
• No

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Version of ClosedXML 0.95.4

What is the current behavior? If I execute the code worksheet.Columns().AdjustToContents() with 10’000 rows it takes more than 20 minutes (I stopped it).

What is the expected behavior or new feature? It should takes about an half seconds (as Excel does).

Is this a regression from the previous version? I don’t know.

Regressions get higher priority. Test against the latest build of the previous minor version. For example, if you experience a problem on v0.95.3, check whether it the problem occurred in v0.94.2 too.

Reproducibility

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Code to reproduce problem:

public void Main()
{
            var workbook = new XLWorkbook();
            var worksheet = workbook.Worksheets.Add("Dati");

            DataGenerationWithBigData();

            worksheet.Columns().AdjustToContents();

            worksheet.PageSetup.PageOrientation = XLPageOrientation.Portrait;
            worksheet.PageSetup.PaperSize = XLPaperSize.A4Paper;

            workbook.CalculateMode = XLCalculateMode.Auto;

            workbook.SaveAs(workbookFile);
}

• I attached a sample spreadsheet. (You can drag files on to this issue)

[Pitterling]

@Netclick19 … you know you could limit that by yourself …

//startRow=1, endRow=100
.Columns().AdjustToContents(1,100);

[SirMeowington]

I just want to add that the AdjustToContents() method still takes a seemingly exorbitant amount of time. 10,000 rows with 32 columns (most of them populated with varying lengths of text) takes the AdjustToContents() method approximately 1 minute 17 seconds, or 130 rows per second. 250,000 rows took 31 minutes 15 seconds (133 rows per second).

This was measured by a System.Diagnostics.Stopwatch object that was started immediately before and stopped immediately after the AdjustToContents() method was called.

using (XLWorkbook wb = new())
{
     IXLWorksheet employeeSheet = wb.Worksheets.Add("Employee");
     IXLRange employeeDataRange = employeeSheet.Cell(1, 1).InsertTable(resultsFile.EmployeeRecords); //EmployeeRecords is an IEnumerable<T> collection which only takes a couple seconds for the InsertTable() method to handle.
     Stopwatch sw = new();
     sw.Start();
     employeeSheet.Columns().AdjustToContents();
     sw.Stop();
     wb.SaveAs("TestBook.xlsx");
}

In case it’s helpful: Visual Studio 2022 .NET 6.0 ClosedXML v0.100.3 ExcelNumberFormat v1.1.0 OS: Windows Server 2019 CPU: Dual 3.00 GHz Intel Xeon® Gold 6284R RAM: 64 GB HDD: Solid state