rdisp/debug_jvm_startup is a SAP Parameter attribute which is used to control debug java vm startup 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 parameter makes it possible to activate the Java Debugging while
starting up a VM of the VMC (Virutal Machine Container) as early as
possible. Different VM types (REM, AUTOJAVA) can be specified. Aside
from this it must be specified if the debugging is to be activated just
once or every time a relevant VM is started.
Syntax
rdisp/debug_jvm_startup = <(><<)>VM Type>=<(><<)>Debug Mode>, .. <(>
<<)>VM Type> = REM | AUTOJAVA <(><<)>Debug Mode> = ALWAYS | ONCE
Example
rdisp/debug_jvm_startup = REM=ONCE
When starting a VM of type REM for the first time, the Java debugging is
activated, all other VMs of type REM are started without debugging.
rdisp/debug_jvm_startup = AUTOJAVA=ALWAYS, REM=ONCE
Debugging is activated whenever a VM of type AUTOJAVA is started.
Debugging is only activated simultaneously when a VM of type REM is
started.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.