Replace std::endl with '\n’ in buffered output operations
std::endl
flushes the buffer it writes to _immediately_! That means every line is written separately to the file. Because we use it everywhere we have a big performance hit when e.g. writing data to files.
I stumbled across this thanks to Marc because his ogs-5 jobs on the eve cluster were killed because of exceeding IO-operations.
See these StackOverflow discussions:
And the std:endl documentation.
The use of '\n’
seems to be platform independent but we have to research that.