Cache files option and performance

I have one more little question: when using nero burning rom in order to burn a dvd-rom iso in the tab misc you find a flag for cache files from disk and network. Which would be the equivalent in nero sdk using vb? leaving it unflagged would increase performance? I have a program that gets a few thousends (3k or more) of pdf files from the lan and then burns a dvd in the local computer that is running way too slow, 3 or 4 times slower than doing the same action using nero burning rom…
any help
thank you