rdisp/vb_lock_mode is a SAP Parameter attribute which is used to control Handling of SAP enqueues after update error 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 .
Thsi parameter defines the handling of SAP locks inherited by the update
after update failures. There are three
variants
for releasing the locks again. After update failures is should be
avoided that important system resources remain locked. The parameter for
this variant is RELEASE.
These locks remain. The parameter value for this variant is HOLD.
The locks are only retained if the update was triggered externally and
the status was previously PREPARE. The parameter for this variant is
HOLD_AFTER_PREPARE.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.