Reading 50Mb Excel File Consumes 12GB Memory!

[chaojian-zhang]

To replicate:

1. Create an excel file
2. Populate 4000 rows by 4000 columns of values and simply fill it with any number you like, e.g. 150
3. Save the file

The file should be around 50Mb.

Now, with a new C# .Net 6.0 console project, load the file using the library as below:

using (FastExcel.FastExcel fastExcel = new FastExcel.FastExcel(new FileInfo(filepath), true))
{
    var sheet = fastExcel.Read(1);
    sheet.Read();
}

In DEBUG mode, it consumes more than 12 Gb of memory just to read 4000*4000 values! (And it took almost 2 minutes to read on Lenovo P1 Gen 2)

By my calculation, even assume those numbers are stored as double (8 bytes), it shouldn't take so much memory: $400040008/1024^3 = 0.1192$

Thanks!