Enabling xplink in the runtime environment and compiling applications
with xplink enabled improves performance in z/OS® V1R2.
- For best performance, use the LPALSTxx parmlib member to ensure that LE
and C++ runtimes are loaded into LPA, as shown in the following example:
Example:
sys1.parmlib(LPALSTxx):
********************************* Top of Data ********************
USER.LPALIB,
ISF.SISFLPA, SDSF
CEE.SCEELPA,
LANGUAGE ENVIRONMENT
CBC.SCLBDLL, C++ RUNTIME
.
.
.
******************************** Bottom of Data ******************
- Ensure that the Language Environment® data sets, SCEERUN
and SCEERUN2, are authorized to enable xplink.
For processes that run the
client ORB, since they start the JVM, must run with xplink (on). For best
performance, compile applications that use JNI services with xplink enabled.
Compiling applications with xplink enabled improves performance in z/OS V1R2. As
you move from z/OS V1R2
to z/OS V1R6
you should experience additional performance improvements when all of the
LE services calls are xplink enabled.
- Ensure that you are NOT using the following options during production:
- RPTSTG(ON)
- RPTOPTS(ON)
- HEAPCHK(ON)
- Turn LE heappools on.
If you are running a client on z/OS, setting
the following: SET LEPARM='HEAPP(ON)' in a shell script,
turns on LE heappools, which should improve the performance of the client.
- Refer to Fine tuning the LE heap
Customization Note: Do not modify LE parameters
without consulting IBM® support. The LE parameters are set internally to
ensure the best possible performance of the WebSphere® Application Server, which
is the main LE application running in the address space. If you need to add
or change LE parameters, make sure that you work with the IBM WebSphere support
team to ensure that the internally set parameters are not compromised. The
appropriate interface for making these changes is through the PARM= parameter
of the EXEC PGM=BPXBATSL statement in the startup JCL.