Memory 
 
The third menu, Memory, leads you to a window where you may specify how much memory (RAM) the program is allowed to use. Both during splitting and restoring, the program reads a certain amount of data from the input file into memory, writes this data from memory out to the output file, and repeats this procedure until finished with a smaller file. The whole procedure is then repeated for the next smaller file until done with all files. The more available memory, the less switches between reading and writing will be necessary. This amount is specified here. 
 
 
 
The third menu, Memory, leads you to a window where you may specify how much memory (RAM) the program is allowed to use. Both during splitting and restoring, the program reads a certain amount of data from the input file into memory, writes this data from memory out to the output file, and repeats this procedure until finished with a smaller file. The whole procedure is then repeated for the next smaller file until done with all files. The more available memory, the less switches between reading and writing will be necessary. This amount is specified here. 
 
Nevertheless, the default values cannot possibly be the best in all cases, so you are free to experiment with these parameters, to optimize the program. However, to really gain any significant speed by altering these parameters, the files should be quite large, say more than 50MB, but having files of several GB, you should definitely experiment. Note that you can always interrupt the program using the seventh button from the left (and then restart after changing some parameters).