Why 2Gb, 3 millions rows, 10 columns CSV file needed 4 hours to be opened by LibreOffice Calc on Core i7 when only 10 minutes needed for php script to open it, convert into 2 dimensions array, make some edits and save?

[mirosas]

I’ve created 2gb, 3M rows, 10 columns csv file. Then tried it to open with LibreOffice Calc, and… after 4 hours it was opened. Why so long?

I’ve also opened this file, converted to 2 dimensions array, made some edits, and saved to csv using php script in 10 minutes. So… I expected that office software written on C++, that can easily use multitreading should work at least 20x faster then single threaded php script, but actually it works 20x slower… why??

while (($data[] = fgetcsv($source_h,0,’,’,’"’,"\0")) !== FALSE) //i used this to parse csv file with php

[Cookievore]

And the LO Version you used is? Latest versions have received some significant performance improvements.

[erAck]

Because it’s two completely different technologies, Calc is not just a two-dimensional array to read strings into.