vmcj/option/ps is a SAP Parameter attribute which is used to control poolsize for the VMC 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 .
This option specifies the poolsize of the VM Container. The poolsize
is a memory shared between all VMs and is used for shared data (e.g.
shared classes, shared closures #).
See SAP Parameter Documentation for full SAP documentation for this profile parameter.