abap/pxa is a SAP Parameter attribute which is used to control Mode of Operation of Program Buffer 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 .
DParameter influences behavior of program buffer
It can have following values:
shared
program buffer is used by all work processes;
default, cannot be changed
gen_local
ABAP programs are generated in user LUW
gen_local_in_dialog
ABAP programs are generated in dialog processes
within the user LUW and in other processes within
their own LUW.
gen_remote
where possible, ABAP programs are always generated
in their own LUW; default value
protect
program buffer is protected from being
overwritten; this addition only has an effect on
NT, HP-UNIX und SOLARIS
use_semaphore
semaphores are used to lock the program
buffer; default on NT
use_mutex
mutexes are used to lock the program
buffers; default on all other platforms
develop
as a rule, a database commit is triggered after an
ABAP program is generated.
Because this additional database commit influences
the behavior of an application, the addition cannot
be used in a
productive system. In a development system,
this additional reduces the likelihood of
database
deadlocks.
generate
This addition ensures that ABAP programs
are, as a rule, generated only before they
are used. For diagnostic purposes only.
source
ABAP sources are also loaded into the program
buffer.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.