Hi
For RTCS, file rtcscfg.h contains the definitions for configuring optional features in RTCS. You can disable the features you don't need.
FTP, TFTP, HTTP protocols are not linked if their routines are not called.
There are other options in order to reduce the RAM utilization.
You can review from the MQXRTCSUG.pdf file the chapter 8 "compile-time options" for more details
Regards
Daniel