abap/use_paging is a SAP Parameter attribute which is used to control activation switch information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
Value 0 New memory management is active Value 1 New memory management is inactive, SAP paging (old memory management) activated
See SAP Parameter Documentation for full SAP documentation for this profile parameter.