axlsx vs simple_xlsx

simple_xlsx:

text = getRandomString(15)

serializer = SimpleXlsx::Serializer.new("test2.xlsx") do |doc|

  doc.add_sheet("Report") do |sheet|

    (1...3000).map{

      row = []

      (1...1800).map{

        row.push text

      }

      sheet.add_row row 

    }

  end

end

axlsx:

text = getRandomString(15)

package = Axlsx::Package.new

workbook = package.workbook

workbook.add_worksheet(:name=>"Report") do |sheet|

  (1...3000).map{

    row = []

    (1...1800).map{

      row.push text

    }

    sheet.add_row row 

  }

end

package.serialize("test.xlsx")

Results:

simple_xlsx:
Memory Usage: 17836kb, elapsed: 61.828213seconds.
axlsx:
Memory Usage: 2118256kb, elapsed: 177.089469seconds.

17+Mb vs 2+Gb, 61s vs 177s

File output seems to result in same size: 14+Mb

it would be nice if axlsx could write to file directly instead of serialize in the end.